Rapture MODing Ideas

* See also Types_of_assets
* See also Player_Created_Asset_Collaboration_System
* See also Player_Created_Assets
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If you can't have a MMORPG ( It is a huge Project requiring real vision and huge resources/effort ), then allow Players creating Levels for a version of the Solo game ...
Skybox substitutions - Basic texture and use Use-Modelling Tools to add '3D' game integratable components  (use the objects from the out in sea Assets).  Also you could use '3D' Assets to help 'draw' static Skybox texture.
Modular 'stuff outside windows'  for quick compositions of various Sea Life thingees that Player wont interact with ( or will if Diving Suits are added to the REDO game ).
Templates for 'Missions' on a created level with text descriptions/explanations/goal_logs, etc...
The usual Trigger placing mechanisms for NPC Spawns and effect activations.
'Wizard''Wizard' type program user experience is one where the user is led through a set of inputs/choices with alot of guidance and help/explanations for the task. driven "Finite State Machine" (another Template) to control 'Spawns' and various effects ( via 'triggers' to do transitions to the next 'states' sequence of events ).
Portals to another 'level'A unitized game world/terrain setting, which fits within the computer's memory, and which is switched between with a data loading delay. ( versus a continuous 'world' type game where additional scenery is loaded 'On-the-Fly', while the Players is still playing normally ). ( loading a file to a start/entry point, without losing the Player's 'State', saving the old game terrain level's 'State' to allow a Campaign or simply larger multi-level Scenario Map ).
'Building Block' terrain using existing Solo game 'rooms',  but allow some variable changes to textures ( the easiest part to Edit ), color themes, and lighting parameters, and various effects like water/sparks/fires.
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RAPTURE FOREVER -- MODding instead of MMORPG .....
Lowered Expectations -- reality is what it is:
This revolutionary MMORPG of my vision isn't likely to happen - This 2K Company simply is not capable of it ( with all the fancy new features, it would be required to be MORE than some generic lame 'run-of-the-mill' MMOMMO = Massively Multiplayer Online ).  Maybe 10 years on, when a dozen other companies are already using the new Player Creation MMO systems/methodologies ( after the processes are proven and profits are being made ), they (2K/Whoever then owns the Rights ) can look back and remember how popular BioShock/Rapture was as a genre.
But long before then, here's something 2K/IG/whoever might actually have a chance to make happen :
Not Massive, probably Multiplayer (and Solo) First Person Shooter (NM-MPS-FPS ) with PLAYER level MOD creation for the same/similar/existing game engine. A modified BioShock game program that accepts mod'ed levels for Solo and Multiplayer (same Unreal 2.5 - no need to upgrade) -- Reuse much of the programming already done (saving big $$$)
Modding tools to create 'levels'- will cost $$$, but such interfaces have been done before and there wont be much 'reinventing the wheel' (maybe Unreal already has tools that can cover more than a little of this - saving some $$)
Reuse asset data from the BS1/BS2/MP/DLC games ( weapon/physics/lighting mechanics/props - both objects and terrain/NPCs/Terrain rooms ) to save alot of $$$$$$$$$$$$$. Use pretty much the same game  mechanics/interface options as were in the solo games. There is alot there already existing to make use of, even without creating ANYTHING new or players having to create complex assets themselves ( stuff like  texture substitutions are 'easy' ). Just recombine the existing elements ( chopped up fine enough into building blocks ) to allow crafting completely new scenarios ...... Using a placement editor, exposing  scripting for the more complicated bits if needed. Dialog Editor ( See description of that in the MMORPG wall of text posting )
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Tap Into The Players Creative Imagination.
The best part of the BioShock games were when you first arrived and had never seen the places you are led thru before, and had things jump out at you ( without already knowing where EVERYTHING was after the 6th replay ).  Dark and creepy.  New mod'd content could give you that feeling again.  Yes, there would be alot of wannabee/unimaginative garbage to wade thru ( as always with MOD'd games ) and discard ( that's what online forums are for ), but some Players are REALLY good, and can create level scenarios superior to what we got in the published games.
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Required Features:
Level builder tools to place and combine those building block thingees (preferably easy to use/visualize)
MP mechanism that allow use of new MP levels and provides same MP scenario game mechanics ( AND BETTER --- add NPC capability so that cooperative scenarios could be made ).
Open Level publishing/distribution model same as done with so many other mod'able systems (mod pack system for any NEW assets)
Allow chaining of levels to facilitate bigger (multi-level) scenarios ( for stuff that don't all fit on one level - also handy to simplify for Platform performance ).
Platforms ?? How different/difficult to allow playing the new levels ( if not run the creation tools which might only be on the PC ) ??? Was the data really so different between the platform versions of the game ( and we aren't changing the game programs that much - hopefully ). Could the level 'baking' tools handle this without players having to do the heavy lifting??
MAYBE have a Player run persistent Multi-Player Server system like "Neverwinter Nightshttps://nwn.fandom.com/wiki/Neverwinter_Nights" had -- BUT with "program support" -- with a program level interface to the game engine), this time to allow Players to do more Server World customizing and building things the company never bothered to provide (like the 'Bank' storage, cross level transfers of characters, spawn controls, AND external AI programming ( in place of their abominable scripting language, multi server support ), etc ...
A separate/improved lobby system from that buggy 'Live' interface.
Company would provide a sampling of 'levels' to act as templates/project skeletons for easier mod build ups. These would also serve as the test scenarios that would be used (in-company) to make sure that the system did what it was supposed to and be not too buggy for Players to use. They would also allow it to be sold as a stand-alone product with a number of pre-made scenarios making it worth it to people uninterested in getting 'levels' externally (the better Player created levels could be periodically vetted and packaged for patch distribution (NOT as DLC PLEASE).
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Broader appeal (We gots to sell this thing to some company and THEY are taking a Risk, after all):
Simple 'Unreal Tournament 2000 like' scenarios (solo or MP) would obviously be possible with the usual MP style cut-down circular level maps ( a decent AI for the NPC opponents probably could be done by a few good Players - IF the company doesn't want to spend the $$$ for that ).
* Cooperative MP scenarios ( NPCs running in MP - they don't have to be genius AI )
* Modding community obviously (with player tutorials, level distribution, commentaries, etc...)
* Nostalgia from players who wished to visit Rapture one last time...
* Name..... Call it "RAPTURE FOREVER" .... or "RAPTURE XTREME !!!!"
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What really matters to the company to make this happen --- $$$$$$$$$$$$$$$$$$$$$$$$$$$$ :
Would this be (alot) cheaper than creating a new Solo game in yet another sorta-BioShock genre ???  ( Meaning would there be a profit in reselling the same Rapture genre in this form ?? )
How hard (as in effort/cost) would these Tools be to develop AND required changes to the game programs AND  the assets slice/dice ( off-shore that tedious job to India/China to be done at a fraction of the  cost ???? ).
After Infinite is done and gone, they might look for a 'quickee' project to make a few bucks off the Rapture BioShock branding.
Get another studio to do it ???
I suppose they could do the same to Infinite ( separate engine, separate project )
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I would guess it wouldn't be too difficult to do what Neverwinter Nights did long ago :
An editor that had terrain building blocks (rectangular of different sizes) that were sections or rooms and caves and chunks of outside scenery that fit together ( unfortunately in WAY too regular patterns ). The terrain blocks were pre-detailed (no real substitutions for wall textures -- pre-made with mesh and texture). There were props single or clusters that could be placed on the floor space and rotated.
'2D' grid maps (upto some max N x M size) were made of those matched up blocks and you used portals to connect any simulated 3rd dimension or to expand the network of grid maps for the 'world'.
Wizard created spawn points, lights, sound effects, triggers and such were placed. Dialog trees could be created and attached to NPC (porps) or other objects. Scripting could be added for triggered events ( also embedded in Dialogues to do many things including acting out Cutscenes ).
The level would be baked and a resulting file could be downloaded for a Player to use solo or in an Online player-run server world running the same file. They were dependent on an asset library of all the building blocks, props, sound effects etc ... Those libraries could be customized with some player created objects ( Player would have to DL (download) file and install ). Eventually the game company took submissions and built patches to the standard object library ( with quite alot of additional terrain and props that the original game had).
Even if some further customizations are available, large sections might be genericized - leaving more overall effort available for the customization 'special flavor' portions of a scenario.
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I would hope with the greater processing power/memory/GPU that more versatile building terrain blocks could be used (more wall texture substitutions, placeable details (even if they had to be placed in predefined 'slots') instead of the static (and very boring/limited) ones in that old (Neverwinter Nights) game. Allow MUCH larger grid maps and the ability to go '3D' overlapping levels would make for less boring terrain creations.
Placement of objects would be similar (but please have an editor that you can get a Point-Of-View IN the editor from where the players would stand/walk around to see what the terrain really looks like (instead  of a god view). Objects with predefined standard behavior scripting (invoking game mechanics) would also make the terrain building easier (like the oil pools can catch fire...).
The SCRIPTING in Neverwinter was an abomination (horribly slow and a limited scripting language/programming methodology) and had no external interface to have logic processed OUTSIDE of the primary Server machine - Which would allow some better AI you couldn't do using the lame server scripting.
That would allow the talented programmers to control/adjust spawns and direct NPC actions, interactive props, etc ... if they had none of that in the game company provided release.
I recall that Players used the pathetic/low/kludgy Neverwinter script system and rewrote NPC battle behavior logic that was FAR superior than what the game originally (company produced) had.
SO players use existing assets (actually there are ALOT of them that could be available) but can recombine them and tie them together into a variety of plotlines for the 'level' scenario.  From Protector_Trials type mini-scenarios, to large coordinated adventures like Minervas Den.
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The assets would be (slice-n-diced) chopped out of the original Rapture games ( BS1/BS2/MP/DLC ) -- Many may already exist as individual object data as they were replicated on the maps many times.  We had lots of different shapes of interiors that could be slid up to allow them to be expanded/shrunk with the repeating segments.
The original games were largely choreographed (you were led around and some areas were sandboxed, but most advancement was blocked till you played thru the plot events).
One thing that likely would change would be the '[Audio_Diaries|Audio Diary]]' and Radio Message mechanisms would have to allow all text (voice acting might be addable but it takes alot of talent).  Any new NPC quips or plot speeches likewise would have to allow text bubbles.
MIDI or ABC format music should be simple (all company distributed scenarios will be vetted for copyright infringements).
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Multiplayer requires servers (part of that code was already done for MP) but more persistent operations ( than MP scenarios that run for 15 minutes ) might require some modifications -- INCLUDING a Player  character vault (saving the Player state).
Multitudes of different MP type maps (like the existing BS2-MP ones) could be generated, like what was  done for Unreal Tournament.
Small MMORPG type 'Worlds' take alot more work to create (to have a cohesive plotline/environment) and to maintain.
Neverwinter Nights supported 64 players per server simultaneously ( though I never saw any run much above 35 players ). Greater scaling to multiple Server machines for the same 'World' might be another  improvement.
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There would be similar terrain and seafloor prop building blocks to construct many types/arrangements of undersea terrain  ( and slightly different game mechanics in the water ).
So that game aspect can be modded (recombined) and be MUCH more than what you got there in the original games.
That includes building exteriors -- there are lots of those to make use of and logical sub-pieces that can be rearranged to make backdrops in the foreground of the Skyboxes (outside of the grid map).
Similar 'modding' would allow you to create those window views ( if you haven't yet, use the 'fly' and 'ghost' cheats to go outside the windows and see how they are constructed. )
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Thinking again how the building blocks were used in 'Neverwinter Nights' ( and how boring the recombination could become ) that an improvement would be making the ceiling and floors separate from the walls so that not just different walls styles could be substituted ( or walls of different shape of features ( like window sections etc.. ))  BUT also different height sections (premade in standard increments ( stretchable ones might be too difficult/complex to program or build all the data for ) and likely would warp the decorations too much anyway).
Example: take one of our favorite galleries from Dionysus Park and allow shortening or increasing the ceiling height (new) and (previous) making the room shorter in length by taking out a few of the duplicated sections of wall/wall with window on both sides. Of course all the wreckage is omitted and the artsy-fartsy stuff in the middle of the room aren't there as part of the basic 'room'. There is a whole selection of that stuff as separate objects that can be placed ( freestanding or 'damage' embedded in the wall ) as the creator wishes and rubbish and such to be strewn about to make it as grungy as desired.
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I would have the tools able to import ( files which could be transferred between players ) whole assemblages of predefined 'rooms' with props in place (subject to further editing once they are placed). Whole libraries published and local to the Player ( on their pc Client machine) would be available to string terrain together (and the terrain editor likewise can move/shift/rotate whole groups of building blocks at once ).
When you are creating a scenario you would want some generic settings to tie together (because you are building a plot and not trying to win an interior decorating award). Ones I can think of immediately would be 'standard' settings like a Metro station or a Atlantic Express station to start the player off in the scenario. They could be pre-decorated with the typical refuse and junk we normally see ( including the suitcases, ash cans and boxes that the player could pickup a few useful items from at the start of their adventure ).
The 'art' would be to create sufficiently interesting terrain, the balance of opponents and the resources given to the player to get thru the scenario. Story text could be intricate and detailed cutscenes choreographed, but then it is back to the shooting and the explosions and the yelling Splicers.
Of course the same tools could create whole Rapture Cities ( think we got lots of different bits to work with from the original games assets to do that pretty well ).
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Another thing I would have added : More optional terrain pieces that have destroyable sections ( like the ones used for the vent passages and holes in damaged walls ) -- You could definitely use a hole in the floor/ceiling flavor.
A whole variety for vent passages would be nice to flexibly run various paths for Players to take.
Destroyable items are also fun just to mess up when you get bored ( or have a pile of stuff blocking your path ).
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Another idea would be MP games (of the existing kind) that have an alternate 'game rule' mode that has Perma-Death ( until there is just one side left alive ).  I've notice that players play alot more cautiously when there is a more significant repercussion for Rambo style attacks ( the usual running about like maniacs beyond even what insane splicers would do ).  You might have to adjust damage/Hitpoints ( or tighten up the hit accuracy required ) if the players die too fast (and then have to sit out waiting for the 'round' to be resolved).
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A wider range of MP type games ( what other game flavors would be appropriate ?? )
I don't know if a with-NPC-target competitive shooting gallery could be done ( too many MP game logic changes or simply network delays might make it unworkable ).
Definitely 2 (and 4) player scenarios to make games easier to join when the usership gets sparse again ( virtually noone on these days on the PC side ) or in off hours.
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Changing the MP game mechanics to allow NPCs and cooperative play would probably expand it enough to interest alot more players.  Otherwise you get just more maps with largely the same elements ( you might get nice looking recombinations, but those usually are only worth playing once ).  Having maps larger than the typical MP map - as large as a game level would allow exploring (especially for co-op ).
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Not sure how hard/easy getting access to the scripting is with this engine (or the customization of it).  Neverwinter Nights allowed you to script 'cutscenes' using the actually places NPCs and props ( and even the Players Avatar ) to act out various actions ( move to a place, text monologue from NPCs, key off a standard animation sequence, switch activations, etc ... ) but it took alot of programming work to do anything with the clunky language and library they provided for anything complicated to be acted out. Easiest was initial actions/spawns for triggers which allowed making things a little more interactive.
Most of the mod'd game would be reacting to various combinations of opponents in an environment you haven't seen before.
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We have plenty of components to play with between Splicers/Daddies&Sisters/Security devices/Vending Machine/Keyed doors/Weapon&Ammo selection to go along with whatever building terrain/props you are able to cobble together.
Then it is a matter of what kind of interesting scenarios you can come up with besides a gauntlet of interlocking firepower to run thru.  ( Non-Audio Diaries being text messages could be acceptable, Signs as clues, Text Narratives and Splashscreens, etc ... )
* Obstacle course
* Riddles with nasty things behind the other 2 doors
* Fort Apache : Rapture (defensive position being assaulted by countless Splicers)
* Vent crawl
* Survival Scrounge  (traversing and searching)
* Avoidance (no weapon get thru the obstacles to the 'escape exit')
* Boss fight (allows recreation/variations on all the boss fights in the original games)
* Things we would have liked to do - Sofia Lamb hunting (and then strangling)
* Interesting terrain variations - high-rise map, dark sewers, Fights on Trains, Ocean action
* Prison escape (escape from Persephone)
* Hackathon - get them machines to fight for you...
Another MP scenario ( thought of after playing around with throwing Hypnotize orbs around ) would be snowball fights with Blue/Red orbs (very colorful results). Need some kind of scoring or consequences ....
Swatting object with the wrench might make for an interesting "Splicer Golf"
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Separately SELLING of Level Maps is bad if it is Multi-Player ( difficult enough for matching up Players who might have different sets of maps --- and the Metro Pack Fiasco is a good example of its use failing when most MP players never bought it ), doubly so for selling Player-created maps.
Single player DLC might be OK but only for company produced maps ( where you would expect quality for your money) but they would have to compete with player-created maps --- which should ONLY be free and freely distributed like Unreal Tournaments maps/mods were ).
If they are smart, they would defray the cost of the 'development kit' by creating the Game_Editing_Tools and then using it internally to streamline development of the base game scenario and any DLC ( and have a chance to debug it so it is fit for Player use ).
Downloading levels on-the-fly from a server is usually too slow (using the old mechanism). Only if they developed a proper mechanism that encoded from a standard 'asset dictionary' and then quickly baked the level locally ( or could handle on-the-fly progressive/streaming level building ). Downloading levels before running has worked before and would be sufficient.
On-the-fly progressive/streaming level building is a complicated project that I doubt the game company would want to take the risk of trying to develop.
Consoles also might be left behind ( except for next more capable ones ) which might be a 'deal breaker' all by itself
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One of the tools I've seen in some Terrain Editors ( after you place the building block room sections ) is a spray effect that selectively overlays spots in the generic room with details at a finer granularity, including overlapping different effects. For Rapture it would have puddles, leaks, the various gunshot/strike decaling, steam/mists, darkness, burned areas, flames, previously submerged ( glowing coral and barnacles ), litter and grunge and dirt, ice, wood rot and rust. All those can go on in layers and over 'prop' objects inserted into the rooms ( the placeable props ).
You could have the basic room blocks look from Almost-New in appearance to one with all the mess encrusted/piled on to any needed degree.
You can make the same floorplan look completely different. And the tool is actually easy to use - since the editing plugin does all the hard stuff of adding to the Asset data. You would want features like undo and a fairly long history sequence to backtrack thru if needed ( progressive saving of the asset etc ... )
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Rapture Forever Modding Ideas :
There are several ways they could implement a Modding system for BioShock ( of increasing difficulty ) :
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Simplest Mechanism :
Company provides all assets (chopped out of BS1/BS2/MP/DLC )
Terrain :
* Entire 'Rooms' directly from the original games (same trashed appearance) - minimal work for company data almost verbatim with a wide range available from the BS1/BS2/MP/DLC game levels.
* Player selects 'rooms' and joins up doorways - reconnecting the doorways between different rooms ( probably an auto-align tool goody to make that easy )
* Editor allows reorientation (rotation) and positioning ( most rooms seem to match a cartesian axis system ).
* Variety of short connecting ways (really just small rooms) to interconnect larger rooms. Loop paths may require a few 'flexible'/stretchable 'connection ways' to make multiple paths between same room line up/join correctly.
* 'Breakable' doors can be substituted. Breakable walls only in original spots. Dummy non-doors to cover door portal passages that no longer go anywhere ( were real in game, but now not used ). Security lock doors (hackable/combination)
* Arrangements outside windows in the sea are effectively 'rooms' ( building objects in distance might be handled similarly). Generic Skyboxes out windows (selectable from ones already used in games ).
* Leaks/fire/lights/sparks are ones already built into the original terrain 'rooms' and are NOT changeable ( those have alot of details associated with them ).
Player can place objects within the terrain :
* 'Opponents' :
** Turrets, cameras. (Hacking difficulty can be set)
** Initial NPCs, ( Position and facings, Splicer types for previous games, with their standard behaviors )
** Patrol pattern/paths for NPC to follow when not interacting with players
** NPC spawn points
** All NPCs - player can set their inventory contents
** Preplaced 'traps' trapbolts, trap rivets, proximity mines, mini-turrets, Plasmid whirly things
* Weapons to pick up to add to players arsenal
* Vending Machines, PowerToThePeople, Slot machines, U-Invent, Freestanding safes
** Define contents/recipes available
** Safes set into walls ??? ( ones in original assets or remove them )
* Individual inventory objects ( EVE/ADAM/Plasmids/Tonics/food/ammo/etc... laying on floor/tables etc ... )
* Placeable containers with object contents (including corpses)
* Placeable 'movable' objects - chairs, ashcans, fuel barrels, boulders ( things that can be thrown and aren't glued down )
* Audio Diaries with text only messages - but sufficient to fill in 'story' (if any is needed) or for 'clues'
* Decals (textures) to allow placable themed graffiti and 'combination'lock keys (Player creates texture)
* Some 'wall placeables' ( decorations/pictures/posters and such ) to cover up some inevitable defects/mismatches. These are inserted into the rooms static '3D' mesh.
* Area Music selection and weird sounds for 'flavor' ( source objects Jukeboxes, Record-players, Radios, TVs, speakers ... )
* Scenario Data
** Sets positions where player(s) come on the map
** Activating Game mechanics from existing solo and MP scenarios ( selection of 'rule set' that apply )
Levels created would probably be disjoint (mismatched detail themes) but most of game playing is shooting up 'opponents' and collecting resources to use -- so most players wont care.
Level is 'baked' into a pre-built data set ready to be loaded (MP levels usually have far less interactive detail)
* Mesh groupings are solidified - rooms sub-Meshes changed to real coordinates
* Rebuilds the 'Navmesh' that guides movement
* Breaks objects into visibility sets for rendering ( ie- stuff around a corner isn't visible )
* Creates 'map' overview
* Packages all required assets (maybe references to standard 'dictionary')
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Intermediary Features :
Some 'Rooms' sectioned to allow modifying 'middle' sections to increase/decrease Room size ( usually sections are divided at convenient spot where there are repeating patterns in the room layout - so the remaining pieces will fit together ). Add additional middle sections to get bigger.
Room stretching and warping - mutate rooms corner coordinates and entire mesh is adjusted ( including slopes to allow for odder 3D-ish terrain ).
Simple 'standard' triggers -- Preferably NO scripting ( wizard interface used to edit and set attributes )
* Trigger Can activate/spawn objects (like NPCs)
* 'Activation' Switches that open/unlock doors, spawn consumables(objects)
* Elevator mechanisms
NPC Dialog mechanism - text dialog tree with simple navigation ( ie - NPC helps explain mission on map ).  possibly have objective flags that allow different dialog depending on what player has achieved.
New Skyboxes - substitution (which are pretty much just textures you can edit with common tools)
Custom texture editing for walls/ceiling/floor of specific 'rooms' (texture substitutions) Allows recoloring/patterning.
Mass Spray on effects of grunge/dirt/debris/rust/wetness/scorching, etc...). Is largely permanent decal overlay.
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Advanced ( more work for developers to make tools/data work ) :
Terrain 'rooms' are cleaned up and genericized ( defects and many detail objects removed ) - Terrain is 'cleaned up' removing alot of the pre-placed wreckage which then allows editor to add/change such details.
Terrain Detail sections ( ie- Holes in floor/ceiling/walls, various damage, piles/clumps of debris ) may remain as placeable 'chunks' ( if the mesh deformations can be extracted easily ) . They become standard sizes for wall sections, then can be interchanged and allow more variations of interiors. They have to 'meld' with existing 'room' detail.
Leaks/drips/fire/lights/sparks/smoke/mist are separate objects ( they are largely particle effect objects with associated continuous sound effects ). They are placaeble. Water running down walls are a bit different because they are part of the wall surface.
Water puddle/pools of oil/piles of blocking debris are placeable.
'Furniture' that were fixed into terrain are broken out as separate objects ( no longer static part of terrain mesh ) - large dictionary of these objects for player to select and place.
Scripting : ( Scripting language to do much more complex coordinated actions/settings )
* Choreographed 'scripts' that can be triggered that control object and program NPC action sequences
* NPC Dialogs with more complex scripting
* More complex triggering with scripted logic
*Server Mode Program interface - allows external access to data and NPC control so AI can be done by an expert programmer in a native language like C instead of a horrible/slow 'scripting' language/library
* External cluster machines to drive proper AI.
* Player save, inventory save to allow MP persistence
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Rapture Forever Scenario Mod'ing :
What kind of games (scenarios/level) could the players create ( here assuming to use the simplest/intermediary systems provided by the company specified above ) :
Unreal Tournament style MP with players running around (like maniacs) picking up spawned weapons ( with limited ammo, but ammo spawns too ). One 'special' weapon at a time, but I recall there was a default weapon you could swap ( probably would be a pistol in this game or maybe a decent melee weapon ).  Plasmids/Tonics similarly - one at a time, with a limited time span or number of uses - and some distinctive 'power up object to make plain which one they are).
Running around in new maps is the biggest addition for this type of play. Unfortunately much of the normal Solo game terrain was 2 Dimensional and modifying it to be more '3D' would require editing the Assets alot more ( requiring more sophisticated editor the company would rather not pay for ).
But even with that, you could have dozens of good (enuf) new maps that could be used with the original BS2 MP system.
Mixing in NPC opponents (into the MP game) would require navigation clues for NPCs ( like the Unreal Tournament editor had you place ) and a rework of the NPC AI as they were largely based on short range tactics. Having them make use of more of the weapons and even a wider variety of Plasmids would likewise require alot of NEW smart coding of AI ( maybe a proper Program Interface could allow that to be left to the players ).
Single player (or MP cooperative - "Us vs the Map") scenarios would be Solo terrain recycled/recombined (stitching rooms together) with many more combinations of opponents ( Splicers/Security Cameras and Bots, Traps ) being placed. Less of a need for '3D' style terrain. The players would have to fight their way thru to the end goal (or series of them). With basic trigger scripting, the map designer could arrange for those fun choreographed surprise spawns ( better if they are semi-randomized so they don't follow exactly the same script). Multiple paths to the same objective would allow varying play ( something one hopes they do with Infinite BS ).
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As usual ( with player creation in games ) there would be good scenarios/level produce and (alot) of bad/mediocre. But like Unreal Tournament there would be enough gifted/patient producers to turn out popular content that would be played by thousands of other players for years.
New terrain ('3D' editing from scratch) I don't see really happening because of the customizations they put into BioShock ontop of UE2.5 that takes too much integration of too many pieces/scriptings AND a Editor redo that would be too big a project to make it easy-to-use by players.
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http://www.edge-online.com/features/making-bioshock
Reading about the budget that was spent to develop the first BioShock game ( and had much of the work carry over to the second game ), wouldn't it be even better ($$$$$$) for that work to be used for a third time ???  Cut out alot of expenses to produce the next game in the successful series.
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If the mechanism allowed simple DL/installation of levels off the web ( like "Unreal Tournament""Unreal Tournament" - https://archive.org/details/ut-99 they had whole sections of game websites dedicated to levels for the different UT versions ) then the community would take care of itself ( might even foster the Collaboration scheme that I talk about so much to incrementally improve the levels available ).
Perhaps the company could then select the best to package as a group, but it wouldn't be needed ( maybe have contests for the BEST work done for the 'known' scenarios you named ).
I would worry though about how much the company was willing to do (as in spend money) to build a versatile Editor to make freeform levels possible). Possibly the work could be combined in unison with an Editor for Infinite (take some clever melding because of different UE engine targets). Having the company develop some useful experience it could become a feature of other such games in future.
Certainly mod'ing new splicer/player avatars would be relatively simple.
I would still include the 'room stitching' editing, as a path for less capable player creators to get something done (with props and opponent placeables you still have ALOT to be creative with).
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There are all kinds of character development systems for different games, and it would have to match whatever form(s) the game takes.
A short FPS session game obviously has to allow very fast improvements ( probably via 'powerups' on the map ) though I suppose you could have an accumulative mechanism like the BioShock 2 MP ( giving you equivalents but no real huge advantage ).
If they allowed player run persistent MP servers then you could have a longer development, and people running those Servers could change/select the different development policies that would operate on their 'World'. ( Achievements/ mission point system/ etc ... )
The Mod ability means alot of 'themed' and choreographed scenarios could be created and each one might require a different development path and method.
So whatever it would be it should be versatile enough for the scenario/level developer to set it .
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So what would be new in this "Mod'able" version of BioShock (3) ?? ( a possible one, without many of the advanced features I mentioned )
Mostly the same Splicers/Robot Devices/Weapons/Plasmids ( trying to add new ones to the game would cost alot and probably simply be repetitive ). Maybe one new good one of each, just to give something different to experience/play with. Additional monologue snippets for the existing Splicers(MP Testers) to match any new mechanics.
Movement ? With Infinite's more '3D' movement demonstrated, it might be good to increase the up/down moves ( climbing, we already had jump down ). Expanding the Nav Mesh/animations to allow going up piles of junk/ladders/various other handholds. Perhaps more lifting mechanisms (no rollercoasters tho).
The Mod'ing tools and editors and tutorials/documentation of course ( and MANY samples that can get players started by examples to work from/clone ).
The 'Easy-Builder' (I speak of elsewhere) would make creating recombinations of existing BS1/BS2/DLC/MP terrain elements simple enough for most players to use it effectively ( and the object placement is even  simpler ).
There should be at least a few Game Company provided 'Levels' to play thru, while players wait for Mod'd levels to be produced by the creative players. A number of solo and multiply-player scenarios ( both co-op and competitive flavors ) to demonstrate what can be done with the new features ( and also for the Game Company to actually make use of the creation tools to 'proof' them for players use ( and thus have to fix them up properly )).
The online community could be similar to what I describe for the MMORPG, except with alot less Game Company involvement required ( and less strictures on the submission system ). Outside of Company distribution sites would exist ( that the Company isn't liable for when people distribute problematic Assets ) -- The garbage and gold will sift themselves out. The Company run website would facilitate answering questions on how to use the creation system tools and ideas to implement, as well as feedback on player published levels/assets ( and rejection notices for invalid submissions ). Like the MMORPG, collaboration could be done with partially completed assets being shown/transferred to other players.  Contests of various kinds could be done.
The game itself would have more controllable 'game mechanics' with modes to turn on/off various existing features so that a scenario could be customized -- Including preset loadouts for weapons and Plasmids,  power-up type weapon/Plasmids acquisition with changeable loadout limits, damage adjustments ( I would have have lower damage in the BS2 MP to eliminate one-shot-kills and to make melees last longer than 3 seconds ). The varieties of MP scenario rulesets would be expanded upon.
Progressive scenarios would be done by stringing several 'levels' together within the same game session ( have those Bathyspheres/AE trains to do the 'level loading' delays ).
A 'wizard' (attribute/mode setting) interface to program spawns ( along with a waypoint creator for patrol patterns ) would give alot of control inside a created scenario. A dialog-tree editor to choreograph explanations of the 'mission' ( Neverwinter Nights had one 10 years ago, and this one wouldn't need the full scripting inserts features ).
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Biggest thing that might be new/improved ( I talk at length in the MMORPG thread, but it also applies to a simpler mod-able type game system ) would be greatly increasing the involvement/organizing of a Player Community facilitated by breaking the games up into more individual handleable components.  To bring together the efforts of many people more easily.
For many games that are MOD-able, the development results that could be distributed to other players were mostly the creation of gifted individuals who created whole levels, and alot more lesser creations of things like skins for the game actors ( Player an opponent avatars ). Few people had the time/ability to do all the aspects needed for a workable game scenario. The tool difficulty was still high and the partial development data was not easy to transmit to other players for collaboration.
Scenarios/assets were posted which other players would try and then make some commentary/suggestions which  might bring improvements, and others reported bugs that the author would correct. It was still largely the results of individuals and another person could not look in detail at the guts of the scripting and such to find/fix the problems themselves.
Since those times, various Open Source methodologies and tools have been developed which can handle much of the distribution/communication tasks for 'works in progress'. If tools for the individual creation/modifications can be improved to be easier to use/understand/integrate ( and the game mechanism made to facilitate the piecemeal processes - including more testing rigs to exercise/debug subsections and individual components ). This would make it easier to work in a collaborative manner -- without the restrictive extra overhead of communicating problems/bugs to someone else (often poorly) to try to get things fixed.
Such a system also facilitates borrowing and modification - reuse of other peoples efforts ( I speak elsewhere of templates and skeletons that some skilled people build specifically for others to fill out the details on for the final creations ).
In a company run system, rightful attribution of effort and credit could be enforced, but with the ad hoc nature of this lesser collaboration system it would not be. It will simply have to be made plain that anything submitted might be reused and improved by someone else, and for the community to generally recognize the source of useful partial assets.
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Game's setting has lots of Opportunities :
We hardly saw any of Rapture, and the truth is Players potentially have 1000 X the creativity any company can come up with /afford. That creativity has to be turned into proper game assets efficiently and the great difficulty to make that work is what prevents any game company from doing what I propose elsewhere.
Rapture is also large enough to have many stories, and part of the process would be making sure that nothing conflicts with existing lore/canon or is out of genre.
In any case the tools I mention elsewhere in detail could be used for any game ( and having many cheaper niche games may be a workable business model to reuse the tools which would be expensive to develop ).
Unfortunately, the whole system requires alot of advances in game production and processes, which I doubt any existing company could do properly, even if they decided to fund an attempt.
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A partial set of improvements to increase productivity ( preferably with ease-of-use to multiply the number of people able to make it work ).  Doing it "right" includes not having the 'glitches', which is why even creating this limited advancement in tools would be expensive ( and difficult because it requires a quality level beyond what game companies usually think as 'good enuf' ).  Alot of the game Client would have to be rewritten to facilitate the new mod-capable mechanisms so that would be the time to improve that side of the whole mechanism.
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Take the Old Assets (already paid for) :
1) Add a editor of sorts ( new - probably most of the development work ) to allow building levels and player start states
2) Take the old game mechanics ( maybe a little work combining differences of BS1/BS2 ) to use
3) Spit out a quick cheap game that more than a few people are willing to play (and pay) - sufficient company made/approved Sample Levels ( like Unreal Tournament did )
4) Exploit the  players skills/abilities/imagination to recombine things
5) Allow a publishing model so the company is NOT responsible for Vetting content ( no 'official' publishing of levels or download space linked to the company )
6) A few tutorials to get people started ( Players might fill in tutorial text alot better than Company ) and have Forum space setup for the Mod Community
7) BioShock 3 ....
8) PROFITS !!!!!!!!! .....
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