We don't need no witches, let that motherfucker burn.
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Burn motherfucker, burn.
Burning witches isn't as effective in Left 4 Dead as I had originally hoped. Usually they just run after you, screaming, and beat you to a pulp. If you throw a Molotov Cocktail first, they run after you screaming and beat you to a pulp, while on fire.
Still, much more fun with a very tactically minded team than with strangers online.