I beat the bosses in the first three chambers, no problem defeating them; then I solved three mysteries (it actually read "you hear the lock break" or something like that), but the door to the fourth chamber did not open! I thought it was a glitch, so I tried the quest again... and again... and again...
Second and third time I could not solve the third mystery - the one with obelisks - although it worked when I tried the quest the first time.
Can anybody tell me if it is a glitch, or am I doing something wrong? I've done it about five times now, I am getting sick and tired of the Vault of Ice :)
If you're alone, you may be able to put down a teleport mark, teleport to the Oasis and heal, and then teleport back in, as long as you aren't outside over 30 minutes.