Poor Gary
From Homestar Runner Wiki
Poor Gary is an old, scrawny, flea-ridden horse from the game Peasant's Quest. His sole purpose in the game is to break through the fence leading to the Hidden Glen. Although he is scared of Monster Masks, trying to abuse him in the game will end in death.
In the Peasant's Quest Movie Trailer, he is played by a horse named Moonshadow.
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