Awesome!!!
Permission granted! I want in on these comicky shenanigans of which you speak.

Mauve, Mauve, Mauve.
...Let's face it. There's no way I could possibly write an NPF webcomic and not include you. You are like NPF's resident Left 4 Dead playing, Bill-worshiping, Oregonian goddess. Also, you cast the spells that makes the peoples go boom.
...I think. (What spells can a Mauve Mage cast, anyway?)
Anyway, askin' your permission to include you in the shenanigans.

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That is brilliant.

And of course, just to show everyone who's in charge, Zombie Bill willingly gives up all his guns (because he's so awesome he still remembers how to use an assault rifle even though he's a zombie) and kills the final boss with his bare hands.

And Zombie Bill lived happily ever after!! Or the zombie equivalent of "living," I guess.

Yes. The entire game should be like an L4D version of a Michael Bay movie. Hell, at one point during the last chapter of the game random protagonists from other survivor horror games (Jill Valentine, James Sunderland) should show up and be killed by Zombie-Bill.

...Then have a hodgepodge assortment of the most annoying Final Fantasy characters ever constitute the final boss. They all just stand around, waiting for their "turn" and mugging the camera, and Bill blows them to smithereens.

Make this happen, Valve

I'd play it. But it should be zombie Bill against EVERYTHING.Survivors, tanks, hunters, witches.... Bill destroys them all, only pausing to light a new cigarette.

Because now that he's a zombie, he doesn't have to worry about lung cancer.

...I just want you to remember you've typed that once you're writhing in agony after I unleash my devastating logic on you, Mac.

Anyway, what's particularly sad re: Bill is that the minute I heard rumors that L4D was going to kill off one its eight characters from their two games I knew it would be Bill. I just knew it. For diversity reasons, they'd never kill off a woman or a minority. And the badass elder mentor always dies first.
However, Valve can redeem themselves. Just include an expansion where we can play as Zombie-Bill and kill all the survivors, while making quips about how much they all suck compared to him. We need to make that happen, Mauve. We need to make that happen.

I KNOW! Bill was the bes!! Although I still pretend the other survivors are just waiting for him to respawn somewhere, or waiting for the ai director to drop some chest paddles somewhere. HE IS TOTALLY NOT REALLY DEAD. He's too awesome to die.

I used to be a huge Left 4 Dead fan.
...And then they killed off my favorite character.

WHY, LEFT 4 DEAD?!? Why would you do such a thing?
...Most importantly, why would you kill him off and leave other lesser souls alive?!?

I play Left 4 Dead on a regular basis. I'm pretty good at keeping things from eating my brain by now.

Oh, Mac: No one said you devoured souls.
Hearts, maybe. Brains, most definitely.
But souls? Nah. Not your type.

Mauve, I understand you may be blinded by the sheer ethereal force of your unearthly awesomeness. Nonetheless, you are at risk. Mac's recent strenuous activity on your private message board strongly suggests the possibility that your brain has been infected and is at risk of testing positive for Mac's Disease. I hope you take preliminary precautions to ensure your awesomeness is not thwarted by Mac's plans to devour your cerebrum. (Possibly with ketchup on top and pickles on the sides.)