Bonus dungeon

thumb|250px|Cave of Trials (GBA) from Final Fantasy IV.
A bonus dungeon , also known as a secret dungeon or an optional dungeon, is an optional location that is usually much more difficult than the main game, with enemies that are much higher level than in other parts of the game. These dungeons are considered sidequests and often contain the most powerful equipment and, sometimes, summons that can only be obtained by completing the dungeon. The boss fought at the end of a bonus dungeon is often a superboss.
A game can have multiple bonus dungeons. Bonus dungeons are common features added to remakes of older games to give experienced players new material to test their skills against, and to make the remake a more enticing purchase for players who have already completed an earlier version of the game.
== Appearances ==
=== Final Fantasy ===
==== Soul of Chaos ====
Soul of Chaos is the collective name of the four bonus dungeons originating in the Dawn of Souls version. The bonus dungeons return in the 20th Anniversary Edition, iOS and Windows Phone versions. The Android version or Final Fantasy Pixel Remaster do not have any bonus dungeons.
Each dungeon is tied to one of the four worldly elements and are initially sealed by a statue of their element's respective Chaos Fiend. Each dungeon, with the exception of Earthgift Shrine, is significantly longer than any in the main game. Major bosses from later games in the series are fought in the shrines, and the dungeons include many new and powerful equipment pieces, as well as enemies that were not in the original game.
==== Labyrinth of Time ====
The Labyrinth of Time is the new bonus dungeon in the 20th Anniversary, iOS and Windows Phone versions (but it does not appear in the Android or Pixel Remaster versions). It consists of various floors, each containing a puzzle that must be solved on time to proceed. If the player fails to solve the puzzle in time, a dense fog will invade the area, sapping the party's HP and increasing the encounter rate, and the player will unlock the red seal of the floor when completing the puzzle, which is a sign of failure. Solving the puzzle in time unlocks its blue seal; either way, a passage to the next floor becomes available. Stages become available in a semi-random fashion on each playthrough. At the deepest floor, the player will face Chronodia, Master of Time. Chronodia is a new superboss whose appearance and strength vary depending on how many red and blue seals were unlocked within the labyrinth.
=== Final Fantasy II ===
==== Soul of Rebirth ====
The Soul of Rebirth is a bonus quest in the Dawn of Souls, 20th Anniversary, iOS, and Android versions. It does not appear in Pixel Remaster. It becomes available after completing the game, after which the player can select "Soul of Rebirth" from the menu. Soul of Rebirth gives the player a party consisting of three party members they had in the past, with the addition of Scott. Except for Scott, the members join with whatever spells, equipment and stats they had when they left the party. Each of the characters' ultimate weapons can be found in the dungeon, and at the end of the quest, the player faces the light half of the Emperor.
==== Arcane Labyrinth ====
The Arcane Labyrinth is a set of dungeons in the 20th Anniversary, iOS, and Android versions, but not in the Pixel Remaster version. It consists of a group of three dungeons, each with a set of player-generated floors and a static floor at the end containing only a boss. While they act collectively as a bonus dungeon, the Labyrinths can be entered and completed at any time. When all three are completed, the player gains access to a fourth area called the Arcane Sanctuary, where they may fight bosses and obtain rewards in return. Upon completion, the Sanctuary will be reset, and to re-enter and get a new reward, the player must complete all three Labyrinths again.
=== Final Fantasy III ===
There are numerous optional areas that provide the party with valuable items, including weapons, armor, and spells.
==== Sunken Cave ====
The Sunken Cave is located underwater, beneath the small island to the extreme southeast of the Surface World. The party will need to dive with the Nautilus to reach it. The Sunken Cave has a wealth of chests containing lots of equipment and a few items.
==== Saronia Catacombs ====
This optional area is accessible underwater in the southeast part of Saronia. The party can fight Odin here to obtain the Summon spell Catastro, and steal the Gungnir from him, as well pick up some equipment and items from chests.
==== Lake Dohr ====
Lake Dohr is to the west of Castle Argus over a small mountain range, requiring the Invincible to reach. The party can fight Leviathan here to obtain the summon spell Leviath. The treasure chests here contain a wealth of attack items, as well as some equipment.
==== Bahamut's Lair ====
The cave itself is located to the southeast of Vikings' Cove, but the player must cross the mountains to the east of Bahamut's Lair on the Invincible to reach the entrance. The party can fight Bahamut here to obtain him as a summon.
==== Eureka ====
Eureka contains some of the best equipment. A gateway to it can be found at the bottom floor of the Crystal Tower, but the Eureka Key is required. Doga and Unei unlock the Eureka Key, and give it to the Warriors of Light, granting them access to Eureka, knowing they need better equipment to fight Xande.
==== Iron Giant's Cave ====
??? is an unnamed, secret underwater dungeon present in the 3D remakes. It is named "Iron Giant's Cave" in the 20th Anniversary Ultimanias. To unlock the dungeon, the player must finish the Mognet sidequest and retrieve every letter. Located in the cave are Red Dragon, Green Dragon and Yellow Dragon, which have onion equipment as their common and rare drops, and a secret superboss, the Iron Giant.
=== Final Fantasy IV ===
==== Sylph Cave ====
thumb|Sylph Cave.
The Sylph Cave is located in the northwest corner of the Underworld and is the home of the Sylph fairies. Completing a sidequest involving one of the main characters will earn the player the Sylph Eidolon.
==== Passage of the Eidolon ====
The Passage of the Eidolons links the Underworld to the Feymarch, a town where the player can fight and acquire two new eidolons, Asura and Leviathan.
==== Lair of the Father ====
thumb|Lair of the Father.
The Lair of the Father can be visited as soon as the player has the Lunar Whale and flies to the Red Moon. It is the lair of Bahamut, who can be fought and acquired as an Eidolon. 
==== Cave of Trials ====
thumb|Cave of Trials.
The Cave of Trials is a bonus dungeon appearing in the Advance and Complete Collection releases. It has eight floors and the final floor contains five weapons guarded by bosses, one for each of the five party members the player can swap out. The weapon can only be acquired if the correct member to wield it is in the party. Each weapon corresponds to one of the characters who become available after the Giant of Babil, so as to put them on-par with the rest of the group, who can acquire their ultimate weapons in the Lunar Subterrane. However, still stronger weapons can be acquired in the Lunar Ruins.
==== Lunar Ruins ====
The Lunar Ruins are a bonus dungeon in Final Fantasy IV Advance and Complete Collection, unlocked by completing the game. It has ten sets of randomized floors, although the order of the sets is fixed. Each set, except the last one, has three normal floors and a fourth gateway floor, which contains a save point, a warp back to the surface that allows the player to exit the dungeon, a door that leads to each playable character's trial, and a stairway that leads to the next set of floors. The first three floors of each set are randomly selected from a pool of four or five pre-set floors. The first set also includes an additional entrance floor at the start, where the player gets a tutorial on their first exploration of the dungeon. The tenth and last set does not include a gateway floor, but after going through the first three floors, the player will arrive at the lowest floor of the dungeon (which also contains a save point and a warp back to the surface), where the superboss Zeromus EG awaits them.
The mobile phone version has an all-new "EX Dungeon", which is a remake of the Lunar Ruins.
==== Final Fantasy IV: The After Years ====
===== Challenge Dungeon =====
Every character with their own tale has a Challenge Dungeon. They become available to explore by talking to Challengingway after the tale has been cleared. The Challenge Dungeons are difficult multi-floor dungeons with powerful enemies and often bosses, but for completing them the player receives a rare item or equipment piece. Challenge Dungeons must be completed multiple times to win all the items they offer.
These dungeons are not available in the 3D versions.
=== Final Fantasy V ===
Once the player has resumed control of the airship after obtaining the first tablet from the Pyramid of Moore in the third world, they can ignore the other tablets and go straight to the Interdimensional Rift, the final dungeon of the game. This means that all of the dungeons that are required to visit to unlock the twelve legendary weapons, namely Island Shrine, the Fork Tower, the Great Sea Trench, Sea Floor, Istory Falls and the Castle of Kuza, are technically optional. However, since recovering the legendary weapons is an integral part of the plot, these are usually not considered bonus dungeons.
==== Castle Walse - Watertower ====
Although Castle Walse itself is a mandatory location, it does feature a dungeon-like optional area hidden behind a waterfall where the player can fight Shiva as an optional boss whom, once defeated, can be summoned into battle by the party.
==== Jachol Cave ====
Jachol Cave is accessible in both the first and third worlds. At the end of the cave is a wall that the player character can climb. In the first world, this only leads to a dead-end section on the overworld with no apparent purpose. In the third world, it instead leads to the other side of the locked door in the basement of Castle of Bal, where Odin can be challenged and obtained as a summon.
==== Gil Cave ====
Gil Cave is accessed in the second world, connecting the Kingdom of Bal to the mainland entrance of the Big Bridge. By following a hidden path in the south of the cave, the player can find the Gil Turtle Path. It houses a great treasure of gil, as well as dangerous and extremely powerful Gil Turtles, which are usually encountered every third step. The path may be completed multiple times for more gil.
==== Phoenix Tower ====
The Phoenix Tower is a thirty-floor tower in the third world. Most floors possess two hidden staircases that are revealed upon examining the wall: both lead to the next floor, but one is unguarded, while the other is guarded by a random monster. Every five floors except the thirtieth has pots on the left and right sides of the room: one contains an amount of GP equal to the floor number multiplied by 1000, while the other is revealed to be a Magic Pot.
All encounters apart from the Magic Pots are inescapable, and the enemies tend to hit the party with strong status ailments. Completing the tower awards the Phoenix summon.
==== Sunken Walse Tower ====
Visiting Walse Tower in the first world is mandatory, as it is the original location of the Water Crystal. After the tower has sunken into the sea, the party may choose to visit its ruins once they have access to the submarine in the third world. Since the tower is now underwater, the party can only remain inside for seven minutes, although there are two treasure chests that contain oxygen. At the bottom lies the Mime job crystal shard, which is guarded by Famed Mimic Gogo.
==== Sealed Temple ====
The Sealed Temple is a secret dungeon in the Advance and discontinued 2013 versions. It is located underwater, south of Phantom Village, and houses four crystal shards with the jobs of Cannoneer, Gladiator, Oracle, and Necromancer, although the latter is not received until after the dungeon's main boss, Enuo, is beaten. In the temple, the player can find the strongest enemies and bosses of the game, including Omega Mk.II and Neo Shinryu. The Cloister of the Dead, a battle arena where the player can rebattle most of the bosses, is unlocked by defeating Enuo.
=== Final Fantasy VI ===
In the World of Ruin, visiting any area other than Kefka's Tower after obtaining the Falcon is optional, but doing so allows the player to recruit former as well as new party members. Many players regard the recruiting of all the playable cast before the final battle as canon, and therefore, most areas in the World of Ruin are usually not considered sidequests or bonus dungeons.
==== Ancient Castle ====
thumb|Ancient Castle.
The Ancient Castle is a ruined castle buried between Kohlingen and South Figaro. It is accessible once the Falcon has been obtained. While traveling beneath the sands, the man responsible for Figaro Castle's dive engine will mention they stumbled upon something; the player should decline further movement and go to the prison cells where the cell on the far right will provide the entrance to the Cavern to the Ancient Castle. Many enemies in the area have Reflect status and high Magic Defense.
Inside the Ancient Castle, the player will find the Odin magicite, which can be upgraded to the Raiden magicite in another area of the dungeon. The Blue Dragon, one of the eight legendary dragons, is found in a secret chamber of the castle.
==== Cultists' Tower ====
thumb|Cultists' Tower.
The Cultists' Tower was built by the Cult of Kefka, a group that worships Kefka Palazzo. The tower is the tallest structure in the game with dozens of floors over four screens of staircases. All offensive commands, except Magic, are sealed, and unless Umaro is brought along, the party is limited to the use of spells and items in battle. At the top lies the unique relic Soul of Thamasa, but taking it causes the leader of the cult, the Magic Master, to attack the party.
There are no save points in the tower, and the Holy Dragon, one of the eight legendary dragons, resides in one of the tower's treasure rooms.
==== Dreamscape====
The Dreamscape is a dream world formed from the mind of Cyan Garamonde, and is a reflection of the pain and hardships he has been through. It is accessible when the party rests in Doma Castle in the World in Ruin with a party of four members including Cyan. The Dreamscape is composed of four areas: a void of space with floating walkways connected by doorways; a recreation of the Phantom Train, but with new puzzles involving switches and treasure chests; a mine shaft, seemingly unrelated to a past location in the game; and an exact recreation of Doma Castle, though the party cannot exit the main gate.
Defeating the boss, Wrexsoul, earns the Masamune as well as the Alexander magicite, and teaches Cyan all of his Bushido techniques.
==== Ebot's Rock ====
Ebot's Rock is located north of the town of Thamasa in the World of Ruin. Hidon, the beast Strago and Gungho hunted in their youth, lives there. The cave is dark, and the player only has a small circular area of sight. The player must collect enough Coral from chests to make a talking treasure chest move, allowing access to Hidon's chamber. The player can learn Strago's most powerful Lore from it.
==== Dragons' Den ====
The Dragons' Den is a bonus dungeon in the Advance and subsequent ports, located north of the Dragon's Neck Coliseum on an island with a single tree. Access is given once the player has defeated the eight legendary dragons. The player can obtain the most powerful equipment pieces in the den, guarded by the most powerful bosses.
==== Soul Shrine ====
The Soul Shrine is a bonus dungeon in the Advance and subsequent ports located on a small island near Mobliz. The shrine becomes available after the Dragons' Den and the main story have been completed. The Soul Shrine contains a series of 128 battles against most of the enemies and bosses, including the new dragons from the Dragons' Den.
=== Final Fantasy VII ===
==== Gongaga ====
Gongaga is an optional location which can be visited at any point in the game, and visiting it before Meteor is summoned allows the player to fight a brief boss battle and have access to some unique dialogue. The area is composed of a village as well as three interconnected sub-areas featuring random encounters: a jungle, the Reactor Wasteland, and the Meltdown Reactor. Both the Deathblow and Titan Materia can be found in Gongaga.
==== Shinra Mansion ====
The Shinra Mansion is a building located in Nibelheim with story importance. It is first visited in a flashback after the party has arrived in Kalm, during which the player will not run into any random encounters. It can later be revisited as an optional dungeon after the party has reached Nibelheim, with random encounters and a puzzle which, once solved, allows the player to recruit Vincent.
==== Da-chao Statue====
The Da-chao Statue is the monolithic sculpture sculpted into the mountain overlooking Wutai Village. It is part of Yuffie's sidequest. Although the entire area is optional, this is the only part of it that is dungeon-like and features random encounters.
==== Ancient Forest ====
The Ancient Forest is located in the Cosmo Area and is accessed with a green, black or gold chocobo, or by defeating Ultimate Weapon. In the forest, the player must solve some puzzles to find rare Materia and weapons.
==== Gelnika ====
The sunken Gelnika is a crashed airplane that lies on the Bottom of the Sea to the south of Costa del Sol. The plane can be accessed with the submarine. Even after sinking to the ocean floor, the plane's interior keeps from flooding, allowing for one to enter the sunken aircraft from the ocean. Gelnika holds some of the most difficult random encounters, and also some of its best treasures.
=== Final Fantasy VIII ===
==== Tomb of the Unknown King ====
The Tomb of the Unknown King is a location near Deling City, and by doing the sidequest inside the player can obtain the Guardian Force Brothers. Most of the areas are tunnels, making the tomb appear straightforward, but if the player backtracks, the viewpoint will change, potentially confusing the player. The player will drop a SeeD rank if they venture out of the tomb before the objective is fulfilled.
==== Centra Ruins ====
The Centra Ruins is on the Centra continent. Upon entering the ruins, a timer begins and the party must find a series of red gemstones and place them in the eyes of statues to acquire the secret code to access the room where Odin is fought. The Tonberry King also appears randomly once 20 or more Tonberries have been killed. Defeating him earns the player Tonberry as a Guardian Force.
==== Deep Sea Research Center ====
The Deep Sea Research Center is a hidden island far out in the middle of the ocean, in the very southwest corner of the world map. It is an abandoned, half-sunken laboratory formerly used to research draw effects. In the first area the player must face Bahamut, and after defeating him and earning him as a Guardian Force, the player can advance deeper into the ruins after leaving, talking to a person, and returning.
Some of the toughest opponents are fought on the way to the bottom, and on the last floor the player faces Ultima Weapon, who has the most powerful Guardian Force, Eden.
=== Final Fantasy X ===
==== Cavern of the Stolen Fayth ====
The Cavern of the Stolen Fayth is located in a gorge to the north of the Calm Lands, near the entrance to Mt. Gagazet. The cave hides a fayth that legend says was stolen long ago to prevent summoners from completing their pilgrimage. At the end of the cavern, the player fights a boss, and gets the chance to recruit Yojimbo as an aeon for Yuna. In the International and HD Remaster versions, the party can fight Dark Yojimbo after obtaining the aeon, leaving and reentering the dungeon.
==== Omega Ruins ====
The Omega Ruins is a large dungeon located within a small group of islands to the east of Spira's main continent. Unlike many of the other locations, the cave must be mapped by the player. At the end of the cave, two deadly bosses await the party: Ultima and Omega Weapons.
==== Final Fantasy X-2 ====
Because of the game's non-linear nature, many areas and missions are optional. Completing most of the areas is still needed for 100% story completion, although some areas are truly optional, and do not affect story completion.
===== Ruins Depths =====
The Ruin Depths is an optional dungeon in the Calm Lands, situated behind and on a lower level than the Calm Lands Ruins. It does not have a mini-map, and contains some rare and unique treasures. The dungeon is unlocked by a complicated process of chocobo raising and exploration.
The boss of the area is the Anything Eater. Once it is defeated, all five sets of locked doors open. The final door gives access to the Amazing Chocobo. A Garment Grid with the constant ability of Break HP Limit is the prize for getting to the Amazing Chocobo. The Ruins are not part of 100% completion or the main quest.
===== Fiend Colony =====
The Fiend Colony is an optional dungeon located on the Mi'ihen Highroad. The player must dispatch a level four or five chocobo to the highroad from Clasko's Chocobo Ranch during Chapter 5 to access it. To travel through the dungeon, the player must destroy stone walls with bombs. Once the player reaches the back of the cave, they will fight the King VERMIN!. Defeating him nets a new Garment Grid. Completing Fiend Colony is not needed for 100% story completion.
===== Den of Woe =====
Den of Woe is a hidden cave in the Mushroom Rock Ravine accessed by placing all ten Crimson Spheres on the door. Many of the spheres have special requirements to be obtained and are well hidden. The Den of Woe contains no treasure, but has some boss battles. Although Den of Woe is a sidequest, unlocking and entering the Den is necessary for 100% completion.
===== Via Infinito =====
Via Infinito is a 100-floor dungeon beneath Bevelle. In the final cloister the party can challenge the superboss, Trema. Each cloister block of 20 floors has about 6 level designs that appear at random. The dungeon swarms with monsters, and equipping a Charm Bangle for No Encounters will have no effect. Every oversoulable fiend, except for the Georapella and Precepts Guard, can be found here. Valuable accessories and Crimson Spheres can be obtained from the defeated bosses. Completing Via Infinito adds to story completion.
=== Final Fantasy XII ===
==== Zertinan Caverns ====
The Zertinan Caverns connect the Ogir-Yensa Sandsea and Nam-Yensa Sandsea with the Dalmasca Westersand, as well as the Ozmone Plain in Kerwon. Though the caverns can be visited via the Westersand prior to the events in the sandsea, further access into them will be sealed. The Esper Adrammelech can be found within the caverns.
==== Necrohol of Nabudis ====
The Necrohol of Nabudis was once the capital of the Kingdom of Nabradia, but its remains have become corrupted by the thick Mist that covers the region. The location is not part of the main storyline, and in the original version houses the game's ultimate weapon, the Zodiac Spear. The player can access the area as soon as the Dawn Shard has been acquired, which means that the game's ultimate weapon can be acquired fairly early. The Esper Chaos resides in the Necrohol, as do some marks and rare game. However, the party cannot obtain Chaos until they have at least reached Archades, as one of the items needed to reach him requires a miniquest to be completed there.
==== Nabreus Deadlands ====
The Nabreus Deadlands are connected with the Necrohol of Nabudis, and are likewise accessible via the Salikawood. The sidequest to obtain Chaos involves visiting the Deadlands.
==== Cerobi Steppe ====
The Cerobi Steppe bridges the Tchita Uplands with the Port at Balfonheim. It is possible to access the steppe from the uplands via chocobo. When Balfonheim is visited later, the steppe can be explored freely.
==== Lhusu Mines ====
The Lhusu Mines are a mandatory story location, but its true depths can only be explored after obtaining the Site 11 Key.
==== Henne Mines ====
As with the Lhusu Mines, the depths of the Henne Mines can only be explored after the story events there. Obtaining ten Espers and asking the geomancer in Jahara to open the locked gate within the mines will allow this. The Henne Mines contain some of the toughest regular monsters in the game and the ultimate Esper, Zodiark.
==== Great Crystal ====
Although the Great Crystal is visited as part of the storyline, only a small part of it is mandatory. If the player returns after having obtained the Treaty-Blade, they can travel into the deepest parts of the crystal. The area has no in-game map, and the interior is like a maze with many dead ends and paths that need to be unlocked. The Esper Ultima and the superboss Omega Mark XII reside within the crystal, as well as several rare game.
==== Subterra ====
The Subterra region of the Pharos at Ridorana is located beneath the ground level of the tower. It is explorable after the story events at the Pharos are resolved.
==== Final Fantasy XII: Revenant Wings ====
===== Midlight's Deep =====
Midlight's Deep is a secret dungeon in the US and PAL versions that features the hardest challenges and is located in the Keep of Forgotten Time. It consists of ten levels and the dungeon can be exited at any time, though the party must start back at the first level when reentering. On the tenth and final floor resides the superboss Yiazmat.
After completing Midlight's Deep, Vaan's Anastasia sword gets a boost of +10 in all stats. The stat boosts are cumulative if the player completes Midlight's Deep again.
=== Final Fantasy XIII ===
==== Faultwarrens ====
The Faultwarrens is an optional location on Gran Pulse. It is where the fal'Cie Titan resides breeding increasingly powerful monsters and pitting them against the party. Some of the tougher missions are fought here, for a variety of prizes.
==== Lightning Returns: Final Fantasy XIII ====
The Ultimate Lair is located in the Dead Dunes and can be accessed on the "extra day" via a new Cactuar statue that appears outside the Ruins East Gate. The Lair is full of Last Ones, and is imperative to visit to complete a certain side quest, as it is the only location during a regular playthrough where Meonekton Ω will spawn due to having to kill a prohibitively high number (65,535) of the regular monster otherwise. If Lightning already drove a particular species into extinction, those specimens do not appear.
Within the Ultimate Lair, the game clock does not stop, even during battle, and Chronostasis is disabled. Lightning must keep moving to reach the deepest level. After defeating the enemies on each level she gains access to warp devices that lead to lower floors. On the last floor she can battle the game's superboss, Ereshkigal.
===Final Fantasy XIV===
Most duties are not part of the main storyline and are unlocked via side quests, and completion of the vast majority of raids and hard modes of dungeons are not mandatory to progress the main storyline. The main storyline will often introduce the side quests which lead to optional content and will frequently reference major or minor plot points from optional content, however events and dialogue in the main storyline will change to accommodate the player's completion (or lack thereof) of relevant optional content. Rarely, however, plot elements from optional content will become so critical to the narrative of the main storyline that it will be retroactively made into mandatory content. Thus far only the Crystal Tower raid series has been promoted to the main storyline in this way.
List of bonus duties:
;A Realm Reborn
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=== Final Fantasy XV ===
==== Pitioss Ruins ====
Pitioss Ruins is an unusual dungeon hidden among the mountains to the north-east of the Rock of Ravatogh that can be accessed after the Regalia has been upgraded to the Regalia Type-F.
Unlike other dungeons, Pitioss features no enemies. Instead, Noctis must enter this dungeon alone and complete a series of complex puzzles. For completing the challenging dungeon, the player is rewarded with the Black Hood, though various good items and equipment can be found within.
==== Sealed dungeons ====
Eight of the dungeons found have sealed doors within their depths that hide a secondary dungeon that feature significantly stronger monsters. The sealed doors can be opened after completing the main game and the basic form of the dungeons containing these doors. The player must visit Meldacio Hunter HQ and speak to Ezma Auburnbrie who will present Noctis and his friends with the key to open the sealed dungeon doors.
* Keycatrich Trench
* Balouve Mines
* Greyshire Glacial Grotto
* Fociaugh Hollow
* Steyliff Grove
* Daurell Caverns
* Costlemark Tower
* Crestholm Channels
When the party first comes across a locked door to one of the bonus dungeons, Prompto Argentum remarks that he wishes they had a key that can unlock any door "just like in video games". The Windows and Royal Editions add monoliths to the menace dungeons that extol the stories of rulers of yore seeking to protect their realm from these "menaces".
=== Final Fantasy Tactics ===
==== Midlight's Deep ====
Midlight's Deep is located on an island east of the Port City of Warjilis. It consists of ten levels and is home to the most difficult enemies and the best treasure through the Treasure Hunter ability. Only the first level is initially accessible. To get deeper, the player must fight a random battle, but simply defeating every enemy will not work, instead, the player must find a passageway to the next level that is hidden in one of five different squares on each floor. To find the exit, a unit needs to step on that square. The tenth level holds a regular storyline battle with the secret Lucavi demon Elidibus, who uses the Zodiac summon, which can only be learned from him.
=== Final Fantasy Tactics A2: Grimoire of the Rift ===
Some of the strongest enemies reside in Brightmoon Tor. At the top of each Brightmoon Tor is a watch that have enemies at level 90 and above. Although the items the dungeons contain may only be obtained once, multiple attempts can be made to retrieve them. If one failed to notice them the first time, or simply did not have the required equipment, one can try again.
=== Final Fantasy Type-0 ===
Tower of Agito can be entered via the airship, Setzer, and boasts a hefty challenge. The player must complete five series of battles and defeat 100 of a specific enemy, all of whom are at level 128. The player may access relic terminals prior to entering each challenge, as they cannot leave until all 100 enemies are defeated. Rare accessories are available, with the final prize at the top being the best accessory, the Agito Insignia.
=== Final Fantasy Legend II ===
The Nasty Dungeon features monsters in large variety of groups, and the dungeon has branching pathways with no indication as to which path is the correct one. Enemy groups can easily reach up to fifteen monsters per battle, and surprise attacks can become a constant threat. However, the treasure found inside is well worth the player's effort. The Nasty Dungeon is not strictly optional: the player must enter it to collect the Pegasus just past the entrance. A fairy posted by the chest will warn the player about the danger, advising them to take the MAGI and leave.
=== Final Fantasy Legend III ===
There many optional dungeons to explore found in various areas. Some of them become inaccessible after a certain point. The dungeons are simple to navigate and contains valuable treasures.
* Shipwrecks
* Mushrooms
* West Tower
* Caves
* Shedding of Jorgandr
=== Final Fantasy: The 4 Heroes of Light ===
Holy Tree Tower, Moonsand Ruins, Mysterious Lighthouse and Trial Tower become available after the player obtains the Master Key. Each tower is 100 floors tall with special floors every 10 floors where the player can leave the tower to save. Sometimes the special floors have bosses or a merchant or a treasure chest. Some of the best equipment can only be obtained as random treasures in the bonus dungeons.
===World of Final Fantasy===
;EX Dungeons A, B, C and Z
The EX Dungeons become available after clearing every Intervention quest, then defeating the final boss. Three Gates will appear inside The Girl's Tearoom with the fourth appearing after the others are cleared. Reaching the final area of dungeon Z is the superboss, XG.
;Hidden Dungeon
In the Maxima version, clearing EX Dungeon Z unlocks another bonus dungeon, the Hidden Dungeon. A purple gate will appear on the seventh floor of the Crystal Tower. Each route will have one of the Four Fiends at the end of them: Earth with Lich, Fire with Marilith, Water with Kraken, and Wind with Tiamat. On the final route, the twins will battle all four with the superboss, Garland.
pl:Bonus Dungeon
Category:Locations
Category:Sidequests