Cage Key

The  is a key in Dark Souls.

Overwiew
The Cage key can open several cages in Sen's Fortress:
 * The cage that Big Hat Logan is locked in.
 * A cage that contains a Soul of a Hero in the same area that Big Hat Logan is in.
 * The cage that can be used as an elevator to move through Sen's Fortress.

Obtaining
At the bottom of the tower where the Crestfallen Merchant is, guarded by a Serpent Mage.