Zugo was an infamous house-elf that lived in the 1800's. One night, Zugo's mistress instructed him to "give me something that will put me down for the night." He misinterpreted this order, and gave her a glass of poisoned milk. After realizing that death of a house-elfs master sets them free, he made it his mission to free House-elf kind from enslavement. He went on a killing spree, resulting in the deaths of 33 men and women, before he was apprehended and incarcerated.