Not bad...
Well, I'm giving this a slightly higher score than the "MGS" submission, largely because there were actually some places where this made me laugh (particularly the violence trifecta). It was a pretty decent halloween flash, on the whole, and I can say that I enjoyed watching it.
There were some things that I thought could've been done better, though. The graphics weren't great, but admittedly they aren't really that important in a humour flash like this (though if they were better they might've risen my score a bit). More serious was that the "nerdy" character was an unrealistic stereotype. Now, I don't mind stereotypes if they're spread around equally... but I got the distinct sense here that the other two guys were meant to be "normal" - and since they were voices by more normal-sounding voices, the implication was that you're "normal" as well. If you're going to make your characters stereotypes, spread it around.
It's bad form to make fun of a character type who's different from you in such an obvious way and not do the same thing to the characters who're like yourself. Make fun of yourself, too, not just of people who you think are silly. Try, anyway - it will make your humour more balanced and also funnier.
As for other criticisms... well, some of the jokes just fell flat to me or I thought could've been done better. I can't really make any suggestions for that though - other than to keep writing. You'll get funnier the more you practice at it.
And that's my review. :p
By the way, I must commend you for responding so well even to your critics in the MGS reviews. Not many artists have the restraint.