Carrot Key

From Mother - Wiki on Neoseeker

Carrot Key is a key item in Earthbound. It is used to get into Pink Cloud, the sixth Your Sanctuary.

Obtaining

After reaching Magnet Hill, a treasure box behind the hill holds the Carrot Key. This can be used in Dalaam, where bunny statues are guarding the entrance to the cave of Pink Cloud. After using the key, the item and the statues disappear.