Jarrk

Jarrk was a hobgoblin transmuted into a hook horror in Undermountain in the early 1490s DR.

History
Around the Year of Three Ships Sailing, 1492 DR, Jarrk was a member of the Death's Head Phalanx that went into Arcturiadoom. However, he happened upon one of Arcturia's polymorphing traps and became a hook horror. The other hobgoblins decided to trap it in a room as a joke.