The Rotten Brain is an Pre-Hardmode, Expert Mode-exclusive accessory obtained from the Treasure Bag dropped by The Hive Mind. It will grant a 10% increase to all damage types when below 75% hp, decrease movement speed by 5% when below 50% health and makes shade rain down on you when you are hit. It is also sold by the Dryad after The Perforators are defeated.
- Shade rain deals magic damage and benefits from magic bonuses. However, its damage cannot be increased through any means.
- The shade rain has a base damage of 18.