Blacksmith Dungeon Key

 is a key.

Obtaining

 * Dropped by
 * Dark Baker
 * Dark Miner
 * Dark Smith
 * Crafted by a Handyman (Lv. 20) from
 * 1 Dark Miner's Candle
 * 1 Magnesite
 * 1 Aluminite
 * 1 Ebonite

Uses

 * Access
 * Blacksmith Dungeon