Razor Shell

You strike a creature with a razor sharp shell. Make a melee attack on a creature, dealing 1d12 + MOVE water damage on a hit. On natural attack rolls of 18 or higher, lower the creatures AC by 1. This decrease may be stacked, up to a maximum of -5 to AC.

At Higher Levels: The damage dice roll for this move changes to 2d8 at level 5, 2d12 at level 10, and 6d6 at level 17.