Arena:The Halls of Colossus

Quick Walkthrough
# Go to sleep and be visited again by Ria Silmane.
# Travel to the Mages Guild in Corinth, Elsweyr.
# Go to the Temple of Agamanus and retrieve a stone tablet.
# Return the tablet to the Mages Guild in return for the location of the Halls of Colossus.
# Travel to the Halls of Colossus and recover the fourth piece of the Staff of Chaos.
# Survive an attack from Jagar Tharn's minions.

Detailed Walkthrough
Go to Sleep
As before, go to sleep and see Ria Silmane in your dreams. She will say:

"You have done well. I had thought you lost to me. The third piece of the Staff is yours. Rumors have been whispered about in the Empire. I think Tharn senses that the pieces come together. You must take care to not be discovered by him-your death would be most unpleasant. I have divined the location of the fourth piece of the Staff. It lies in the Halls of Colossus, a structure built to honor a race of Giants, though none have been seen in the land for ages. It is said that the Halls of Colossus sat perched on a cliff overlooking the Great Divide, which is along the southern edge of Tamriel. Perhaps the Halls are near that coastline. I only wish I could offer you more. Fare thee well my friend, and find this place, for the sake of our loved ones..."

Corinth, Part 1
Asking around about the Halls of Colossus leads you eventually to the Mages Guild in Corinth, Elsweyr.  There, the Loremaster of the guild, Turamane ap' Kolthis tells you that they used to have a tablet that would help decipher the location of the Halls of Colossus. They were recently attacked and the tablet was stolen and taken to the Temple of Agamanus.  Most unfortunately, the battle over the tablet left the Guild in a weakened state, too weak to go get it back.   If you agree to go retrieve the tablet, the location of the Temple of Agamanus is marked on your map.

Temple of Agamanus
The temple, located just south of Corinth, is a tri-level dungeon.  The levels are not large, but each contains a good amount of treasure.  The temple is full of flame-throwing monsters and other assorted ill-wishers. You may want to bring some Potions of Resist Fire, because this place is crawling with hell hounds. Also, it could be a good idea to use the opportunity to collect treasures; all levels have a lot. There are several locations that will give you an exploration note that states; "A sign over the stairs reads: Private! Members Only!" These are not necessarily near the stairs, but are intended to help direct you to them.

Upon entering, you will receive a message:

:AGA  NU
:W LCO  S
:PI GRIMS 

:You find a note on this Knight's body,
:-
:You will hold this fortress until my return.
:Guard the treasures well, or forfeit your life...
:Gir Galandir...
:-

Other such messages may pop up in the dungeon, including: 

:The stench of decaying food fills the air.

:A damp, musty odor fills this area.

:The floor here is oddly patterned...

On the first level, the way down is in the southwest corner of the dungeon.  The dungeon has a normal layout, so just head south and west and you'll get there.  There are many small rooms in the very south of the first level which contain easy treasure along with a warning:

:''Clearly some kind of unpleasant rituals were planned for this chapel...

On the second level, you enter in the southwest and the stairway down is in the north center.  The way is indirect.  If you don't have Passwall, you'll initially find yourself threading a little maze and the message:

:A small plaque advises:
:BEAR LEFT - STAY RIGHT

When you emerge, you can then head more or less directly to the way down.

thumb|A tabletOn the third level, you enter in the north center, and the tablet is in the southwest.  Passwall can be a big help, as can Levitation.  Without Passwall, the way is tortuous, and you will have to do some always-dangerous swimming to get where you want to go. There is a very common glitch where you cannot pass a crossing point in the water near the room with the tablet. This is caused by an enemy being directly on top of the wall which sits on top of the water. If you encounter this bug, you can pass through by using passwall to create a path around. If you are not a spellcaster then simply find a weapon at any town that contains the passwall spell as an enchantment. You can also save and reload while directly under the monster, which might change its position and allow you to pass.

When you get to the room with the tablet you'll face the obligatory riddle:
:Answer this riddle and proceed into this vault,
:-
:I daily am in Elsweyr, and in Skyrim,
:At times do all the world explore,
:''Since time began I've held my reign,
:And shall till time is never more.
:I never in my life have strolled
:In garden, field, or park,
:Yet all of these are sad and cold
:''If I'm not there and it is dark...
Answer with "sun" or "the sun", grab the tablet (46,38), and make the long trip back out to Corinth. Nothing happens is you answer wrongly, a correct answer results in the message:

:You have spoken well. Enter...

Upon taking the tablet, you will be informed that:

:''You have found the Tablet Sir Galandir stole from Turamane ap'Kolthis of the Corinth Mages' Guild. When Turamane has it again he can use it to find the location of the legendary Halls of Colossus...

Corinth, Part 2
Back at the Mages Guild, hand in the tablet for your reward: the location of the Halls of Colossus.

Halls of Colossus
"You stand before the gigantic walls of the Halls of Colossus, built by giants in an age long past. The wind echoes mournfully through the empty battlements. Here lies the fourth piece of the Staff of Chaos...''"

The first level of the Halls of Colossus is a very large dungeon that is strewn with keys, and of course monsters.  The keys open magically-locked doors on the second level.  Obviously, the idea is to hunt for the keys so as to get by all the second-level doors. However, by using passwall on the walls around the locked doors it is possible to completely skip this intended portion of the dungeon and run through the Halls in minutes. When first entering, there is an introductory message that is intended to be found on the body you see.  However, the message only appears when standing directly next to it.  It's possible to loot the body from a distance and turn left or right and never receive the note. The map mentioned is not an actual item, but the directions can lead you to the gold key.
:"On this body you find a hastily scribbled note.
:It speaks of finding six keys to unlock the
: . These keys according to a crude
:map seem to be scattered about this level. A red
: 'X' is scribbled on a spot directly north of here.

The monsters on the first level are not too difficult, but the ones on the third level can be more challenging. Monsters include ghouls, skeletons, rats, and a few hell hounds. These monsters are on all levels except the third and last one, where there are mostly skeletons and homonculi (you may want to have a few Potions of Shock Resistance on hand). If you can handle ghouls and zombies, then you should be ready to complete the quest.

The easiest keys to get are the gold and iron keys.  The gold key is on a raised surface just north of the entrance (8,27).  The iron key is on a raised surface west-southwest of the entrance (27,58).

The remaining keys are harder to get.  If you do not have Passwall, you will have to go down to the second level and take the stairs up to enter a section of the dungeon you couldn't otherwise get to.  Take the closest way down (32,52).

The second level is a huge, empty hall (empty except for rats, that is). Upon entering, you are warned of this:

:You enter the secret passage to the Hall of Colossus. The floor here is covered in a fine mold, scratched by large, sharp claws, and the air is warm and moist.

:The dead air in the Hall of Colossus is dry and stinks of decay. In the quietude of the chamber, you can hear the scuffling of many feet. Red eyes stare out at you from the gloom...

Assuming you went down the aforementioned door, the magically-locked doors are directly in front of you to the west.  If you have the iron and gold keys in hand, you can go unlock them if you wish, although you don't need to yet.  More to the point are the other six doors heading up:  three on the north, three on the south.  The eastmost and northeast doors lead to the first section of the first level; the one you're in when you first enter.  The other doors lead to widely-spaced ways up behind the wall that separates the two sections.  The quickest way to the next key is to go through the door in the southeast (37,68).

The sapphire key is on some stairs just north-northwest of where you came up (42,51).  You can from there quickly travel southeast and pick up one of two amethyst keys on a raised area at (22,74).  There's another one, though, so you can skip this one if you wish.  Either way, there's a flooded area in the extreme southeast that you should explore; there's an inscription you would do well to read (7,76)
:There is an inscription engraved here on the moss-caked stone - Theodorus.

From there it's a long swim along the south wall to get to the raised area on which sits the ruby key (69,83).

The two remaining keys are in the far north section, a very long way away from the south section of the dungeon.  You can either make your way there while remaining on the first level, or you can go down to the second level and come up in a closer location.  Going down is recommended because it is more direct.  If you do go down, pick either the north central or northwest door to re-emerge on the first level.  If you don't want to go back down, make your way back to where the sapphire key was and swim west under the walls.

The diamond key is on the floor in an area by a very large pit (72,9).  First unlock a gate north of the pit, then open a door on the west wall and enter a room that is outlined in gray on the map; the key is in the corner of the room.  The other amethyst key is on a raised platform a tiny bit southwest of it as the crow flies, but you can't get there directly without Passwall.  If you haven't already gotten it, make your way around by heading west, then south and back north (79,16).

Now you're done with the first level.  Go down to the second level, open the magically-locked doors (78,52; 82,52; 86,52; 89,52; 93,52), and go down to the third level.

You have one key left: use it to open the first door (94,57).  The next door presents you with a riddle:
:I am the architect of this hell,
:whose name is forgot in the dust of time.
:Yet, where there is no dust,
:where the river would speak,
:there is my name.
:Find this place and then return,
:to tell me my name.
:Only then shall you pass this door.
:What is my name?

Upon answering correctly by writing "Theodorus", you are commended with the words:
:Theodorus, Theodorus is my name.
:Pass, child, and beware the halls ahead.

Failure prompts chastising instead:

:hat is not my name.
:The wisest man would never guess it.
:Search these hallowed halls,
:Make yourself clean,
:Murder that which is dead,
:then give me the name that is true.

Although not your typical riddle, if you explored the first level thoroughly and remember what you saw in the southeast flooded area, you will be able to answer it (the answer is the name of the architect, Theodorus).  If you have Passwall, you can avoid the door and the riddle altogether.  Either way, make your way to the main door.  Inside is a puzzle:
:Answer me this, and prove thy wit,
:for a true challenge is rare indeed.
:I am twice as old as three times the age of
:the Sphinx of Gazia,  ,
:divided by one-ninth the age of
:the Sphinx of Canus, Igon,
:who left this world twenty-six years ago.
:What then is my age?
Solve it using the sum of the index of letters in the alphabet for the age of each name (for example, Igon is 9+7+15+14=45). (The answer to the riddle is 108, hundred and eight and one hundred and eight) to enter the room containing the Staff piece (70,51).

Answering correctly pops up the message:

:You are free to enter, child.
:But be warned - there be devils within.

Otherwise, you receive:

:Impudent child, you may not enter ...
:But you may join those who came before.

You should heed the warning upon answering correctly, as Homunculus with powerful shock attacks fill the area surrounding your prize, though they can be avoided at the cost of the various treasures they guard. Upon entering the next room, another warning is triggered:

:Pedestals hang in the air in this room, defying all laws. Your senses are alert to the acrid stench of brimstone and to the whirring of leathery wings...

If you want to get out of there as quick as possible, run straight forward (east) and a little south to pick up the staff piece, displaying the message:

:The fourth piece of the Staff of Chaos fastens itself to the other three in a flash of blue light. The Staff is now half complete...

Ambush
Upon your next random monster encounter, Jagar Tharn sends a minion and a vision: 
"It is obvious, whoever you are, that you are a cunning and worthy foe. It seems that Ria chose well, even if it was her last act. I will not insult your intelligence with further digression. My minions soon approach, but I will not consign you to the dark door of Death. You have proven your worth. Once you are killed, I will raise you to fight for me, as  . Give in to me now and I offer you everlasting life...''"

Notes
It's possible to avoid traversing the first level of the dungeon for all the keys.
If you have the Skeleton's Key artifact, just go down to the lower levels and open the doors using the artifact.
If you have a spell or magic item with Passwall, you can proceed by removing the wall next to each door; including the one with the first riddle.
You can bypass the final riddle by getting over the wall between you and the staff piece. In the secret room just to the north, jump on the elevated tiles (86,39) and then use a Running Jump to reach the top of the east wall. You may need an increased strength stat in order to make the jump and you should save first; in case you get stuck in the wall. After collecting the staff piece, the door will still be magically locked, and you won't receive the riddle from the inside.  In order to exit the area, you must make your way back on top and over the wall.  There are many options and the elevated platform at (78,30) can provide a first step.
The Halls of Colossus can be found in the Lore section for more information and references in future games.

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