I've enjoyed this series thoroughly, and I think this is a good episode to go out on, as much as I'll miss it.
I actually didn't scroll down before watching, so I had no idea there were this many guest voice actors in this. That's a really impressive cast list, with quite a few of my favorite voice actors and Flash artists! I have no idea how you managed to get them all for this, even if it was just for a line or two.
Violence doesn't usually suit my taste for a punchline, but this Flash was still very entertaining. While much of that comedy was taken from the brief appearances of each character, there was still enough of your own humor to rely on. Also, having the actual creators and voice actors for each character really kept it from just seeming like a typical "I hate ____, so let's kill them" Flash. It's obvious you enjoy their work and that it's all in good fun.
Art and animation weren't your best, but were solid. The bits with Tom were a nice touch, as were the parts with SBC. The only thing that irks me is that you didn't manage to get Krinkels to do anything for this, given the fact that it's Madness day! Given the cast of cameos you already have, that's really just nitpicking on my part.
You made a quality Flash cartoon here, and I hope it wins one of the daily awards. I envy how fast you're able to crank out all these great cartoons.