You can wipe out all The slegs and the Jailer without leaving the room that leads you into the circular prison room. Best of all, you can have the really big Slegs do some of the dirty work for you. First, get as heavily armed as possibly by breaking all the crates and gathering anything you can use before hitting the switch to open the door. Weapons of choice here are both the explosive arrows and rocket launcher and grenades. Use them in that order if possible. You will need the grenades later in a key point. With luck, you started this level healthy and did not need to get the large med-kit at the start. Being able to return and use it is a big bonus. Begin your assault without entering the big prison area. After you strike your first blow, fall back into the room and wait for them to come to you. Hold them back by taking them out in the hallway. You need to survive up to the fifth wave. Next, head back into the tunnels. As you arrive at the first room with the grated floor above, you will probably see two big Slegs. Leave them and wait for the gigantic Sleg to appear. Once he appears, he will proceed to squash the other Slegs. Wait for the other Slegs to arrive. After the other Slegs arrive, they will all just stand there (including the gigantic Sleg). As you move, the giant Sleg will follow. Guide him to the other Slegs and they too will be squashed. Continue this until the giant Sleg refuses to play anymore. Them take out your spiked grenades. Stick them under the feet of any that remain, then back off and watch them go down. When you get to the Jailer, it will require about five grenades to kill. Return to the beginning to replenish on grenades and health if needed. Once the Jailer is gone, you have the entire prison area's stash of weapons at your disposal.