Yes. I want to thank Minime for pointing out this interesting situation. I hadn't responded because I needed to get a game into the right position to test this out...I of course like everyone else always got out of the arena as the githyanki suggested.
I tried (as mini me suggested) instead attacking the giths as they meditated in the arena. (they are worth 2000 or so each) After killing them I was transported back to the holding cell. Soon the ogre guard came and took me to fight more umber hulks. I didn't have time to see how many umber hulk fights you will get right now, so I first wanted to see if you can get out of the arena at all. I know that the slayer can open the other unopenable doors in the flayer lair, so while my other characters fought the hulks I changed into the slayer and sure enough the door out of the arena opened.
I went to fight the ogre guard (toughest damn ogre in faerun as far as i know
![Wink ;)](./images/smilies/)
) but as I attacked him, four flayers gated in and attacked me. I managed to win the two front fight (flayers and ogre on one side, umber hulks on the other), and then went to check out the lair, when another group of four flayers gated in! They killed my protagonist unfortunately so I will have to try it again, but
THE UPSHOT IS: WE MAY HAVE FOUND A BIG OLD FOUNTAIN RIGHT IN THE UNDERDARK!!!!!
I am going to keep testing this but I want to give props to mini-me for finding this!!!
May you walk on warrrrm sannd....