The first downloadable content available for the Xbox 360 game Oblivion. Upon its release, there was an uproar in the gaming community due to its nearly useless feature set and and relatively high price tag ($2.50 US). Since then, the term horse armor has been used to describe video game features that are useless or overpriced.
Can you believe they're charging $10 extra for the horse armor in Madden 07: Hall of Fame Edition?

It seems like every year video game developers expect us pay $50 for a sequel and all they've added is some horse armor.

by Ironhammer July 14, 2006
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A phrase, used by video gamers, meaning "useless purchase". Derived from "Elder Scrolls IV: Oblivion", where decorative horse armor can be purchased for $5.00 online.
Why the hell would you buy that horse armor? Why do you need it?
by Michael Lanter September 14, 2006
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Horse armor is the peculiar sense/emotion of preparing oneself for bestiality (see: anal penetration of a horse or hideous woman).
Mr. Hands should have remembered his horse armor: instead, he received a perforated colon.
by nom de gorilla March 26, 2011
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