Mega Mush is an active item.
- Gigantifies Isaac for a short duration. This effect keeps through rooms.
- While giant, Isaac gains following effects:
- This item allows Isaac to crush metal blocks and tall blocks, which cannot be destroyed by any other means.
- While giant, Isaac cannot use any active items.
- In this case, Mega Mush cannot be recharged by clearing rooms, while other active items gains charges normally.
- Doors of Challenge Rooms, Mini-Boss Rooms and Boss Rooms could not be busted through. Locked doors still needs keys to open.
- Possibly a reference to Mega Mushroom in Mario.