A term used in the game World of Warcraft to describe a Death Knight, since there are so many of them that suck people write them off as being complete failures. You are bound to come across one that sucks.

Fail Knights are popular because they have the advantage of starting at level 55.
Paladin: This death knight rolled need on a shield.
Warlock: haha fail knight
by Puzu September 2, 2009
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