Peacock Island is a sub-area in Metal Lake. It's found in the southeast corner of the lake.
A small island with a cave behind a waterfall. There is a Venus' Bud near the waterfall. Inside the cave there is a stream for the player to climb on, and at the top of the cave the Peacock Spider is fought. Check the sign at the back of the island to unlock a discovery.
- Like Seedling Haven, the description of the respective boss says the main area instead, because the boss would be otherwise too hard to find.