Arcadia Ruins is the last island in the game. The Hero fights Oceanhorn here. The island's location is revealed by Grandmaster Ludwig after the Hero defeats Shadow Mesmeroth, gains the Emblem of Sun and Sky Island goes back to the Uncharted Seas.
- White City
- White City Underground
- Unspawn (Kill 50 Spawn)
- Blockbuster (Destroy 100 wooden crates)
- Vitality (Get all 8 heart containers)