Well, after beating all of those hordes i see you are pretty tired, but still it's not the end of our journey to the tower of babel.
As my analyze says, this corridor is a legendary passage to the test tour, which was necessary to pass if someone wanted to enter the glorious city of gilgamesh, that is standing on our way...yes i know, my sensors saw tower of babel, but seems it was a mistake. Too many time travels make me also tired. Anyway, to pass this corridor, just listen to the legend: ''Only disarmed ones have right to pass corridor of pure darkness''. Seems you have to knock off your weapons and go foward. Watch out, this building wasn't named Test just for nothing, in details, many traps and tricky things are awaiting and of course, Mental's forces will join the party, since they know pretty well this legend, they won't save a smallest troop to stop you.
So, about that city, it's a huge metropolis built by people of Gilgamesh to guard tower of babel. To enter it we have to pass incredibly heavy and huge crystal gate, which is placed outside the building, in gateyard. Shortly, move your skinny ass and leave this creepy temple as fast as possible...just kidding, but really i don't want to die by some sort of old babylonian crap... good luck my boy !