• Boulderfist Key
• Item Level 1Disenchants into:
  Not disenchantable
• Quest Item
• Unique
• Use: Unlocks Corki's Prison.
• 1 Charges

Source

This item drops from:

• Boulderfist Crusher in Nagrand
• Boulderfist Mystic in Nagrand

Boulderfist Key as a quest objective

This item is an objective of  [65] HELP!^ω τ ϖ.

External links

• Battle.net (EU)
• Wowhead
• Thottbot
• WoWDB