Frustration...
I'm sorry, but all this game did was piss me off.
They way the grenades bounce makes them rather hard to use.
It takes TWO grenades to kill some one... even when it lands right underneath them.
Sneaking up behind some one is pointless, as soon as you enter the room they start attacking.
It's WAAAAAAAAAY to fuckin hard. I couldn't beat the first level, on easy, with slow bullets.
I even got the the point where I had one guy left, I was at full health, I enter the room *bam* I'm dead. Wow... that was sure fun...