It's not particularly a hall but rather a shack on top of a mountain, literally a mountain, it is very hard for anyone to find due to the drastic weather climate change. Anyway, so Lucifer holds his meetings here with some of his trusted advises but even the most trusted can back stab. So this hall is where his elders and him discuss things and matters that need to be taken care of - - - like how to rule over the neighboring city and it's ridiculous humans.
