Amulet of Makoolu

Each consecutive 20 you roll in combat adds a Puka Shell to your amulet. Once you roll a number other than 20 or 1 the shells snap. On a hit other than 20 each shell adds a d6 to your damage. On a 1 your shells snap and each deals 4 damage to you. If you have 5 shells and roll a 20 the shells snap and each adds a d6 to your damage AFTER the initial damage dice double. Luck feat will not negate the ability triggered on the 1.

Notes: Set: Constitution Score, Buff, Jewelry