A very cool artistic rendering of the zombie versions of Springfield attacking the Simpsons as Apu tries to drive them to the safe zone.
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As part of the Treehouse of Horror XX, Bart kills Skinner as a favor to Willie. Trust us, it made sense in the context of the episode.
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When Marge thinks that Homer is dead, like any good friend, Moe uses his blood to attempt to seduce his recently widowed wife. Oh that Moe.
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The Simpsons Season 21 Episode 4 Quotes

Lisa Simpson in detention? My horoscope told me I'd see something interesting today, but I thought that'd be the horoscope itself

Principal Skinner

Lighten up ladies, it's not cheating if you're wearing a costume

Homer Simpson