I won't go in much detail for the single player since you can try it out with the classic version for free. It's the same, but with a lot more enemies, bonus levels and items. The multiplayer for this game is simply amazing. Each player control a character, but the camera only follow one of them, there is no split screen. It may sound horrible, but it forces you to stay together and try to work as a team. Note that I said "try", because the game is way more difficult, not because there is more enemies and traps, but because there is friendly fire. Communication is key if you're not a fan of getting shot in the back by a clumsy friend armed with a shotgun. Control is essential if you do not want to whip your buddy in a spike. It may sound dump, but half of the fun come from the failure you'll have with your friends. Because there is always a new way to mess up in Spelunky. The nasty part is that there is no online/LAN play, you will need to gather your party of spelunker on your couch and it's sadly not always an option.
I know that roguelike are difficult and involve a lot of luck, but this one goes a bit too far in my opinion. The trap system is pretty interesting since it can help you with healing trap or ruin your game by breaking your only firearm, but there is no way to know until you try one. So if you fall on the trap that break an item, if your gun break and you are not the marine class you are as good as dead since the game isn't possible with the knife of the other class. The sickness system seems interesting at first until you realize that a lot of enemies cause infection at random. I am not sure of the specific, but I think that after X round you have a chance to get better or worst, if you get past lvl5 you die. You are punish by death for being unlucky and item that can cure you are somewhat rare. A good feature would be the different type of weapon. You get the pistol witch is your standard long range one shot moderate damage, a rifle who is a high power pistol, the assault rifle who give you the ability to shot in burst and the shotgun with spread shot. Add to that a bunch of melee weapon and the ability to switch between them instantaneously. The core game is pretty fun and I hope there will be either some kind of mod or balance patch to make it an awesome game.
