First off, the game starts off much cheaper than the first. The UI graphics and level graphics look and feel 90's cheesy in the first level. But once you wade through it, it gets fun. Second, the levels are MUCH MUCH harder for a given difficulty than before. The levels feel much more like a bloody puzzle to be solved than an actual place. One wrong step, and your guy explodes. You'll be mashing the QUICK LOAD key a hundred times per level. Three, SAVE properly OFTEN. Because there's plenty of things in the levels that will screw you over and it's not immediately apparent. You can go through a teleporter, while a guy walks onto the screen? Only to have him kill you when you come back, and have ZERO way to continue the map. Even with cheats, you'll have to reprogram the DOSBOX special keys just to be able to enable invulnerability for a moment so you can survive the "bug." Which is frustrating and completely takes you out of the game experience.
Great game, but PATCH 2.4 included in the game BREAKS 4-player support!