Version 0.29: This article may not be up to date for the latest stable release of Crawl.
Spirit shield is an intrinsic that treats your MP pool as HP, splitting the damage proportionally. This works on all damage sources except the poison status and HP ability costs. Should your MP reach zero, damage will be taken entirely from your HP until at least one MP is restored. HP will not be reduced to 0 before all MP is exhausted. Multiple sources of spirit shield have no extra effect.
Djinn effectively have the opposite of spirit shield, using HP in place of any MP, so spirit shield has no effect.
Damage Reduction Example
If you have 200 HP and 20 MP, an 11 damage attack will reduce your HP by 10 and your MP by 1. Characters with more balanced HP:MP ratios will see much more dramatic reductions to HP loss.
- Playing as a Vine Stalker
- The demonspawn mutation, Mana Shield 2
- Amulet of guardian spirit
- Moon troll leather armour
- Hat of the Bear Spirit
- Prior to 0.26, equipping an item with the spirit shield ego would reduce your current MP to 0, even if you weren't a Deep Dwarf.
- Prior to 0.25, scarves could have the spirit shield ego.
- Prior to 0.20, hats could have the spirit shield ego. Scarves recieved it in their stead.
- Prior to 0.10, spirit shield would fully consume MP before you started losing health, making it less useful for casters.