Changelog:
+Added some additional rockets for a few rooms
-Changed/removed some non-arena monsters on lower difficulties
~Replaced two 'Cell Stash' secrets with Lightning Guns (the cell stashes were mostly a holdover from a previous version, so they are/were a bit redundant in retrospect)
~Changed some spiral staircase textures to match the other staircase (a crisis averted, this one)
~Tried to flatten out the cave floor a bit (mostly to try and prevent a 'quicksand' situation)
~Fixed some odd brushes I missed in the cave area
