Moon Shell

This is where the werewolf and merfolk lines stop costing you two slots. Night turns you into the wolf, water or honey turns you into the merfolk, and stepping into a lake after dark swaps you from one to the other and back again when you climb out.

The wolf half leans melee, but the defense, regeneration and movement it hands out are class neutral, so nobody should skip it on that basis. The merfolk half quietly removes drowning from the game, which matters more than it sounds during ocean trips, flooded cavern digs and any fishing you do from under the surface.

Half of every day it does nothing at all. Sunrise on dry land leaves you wearing an empty slot until one of the two conditions comes back. That is the argument for pushing on to the Celestial Shell, which keeps everything here and fills in the daytime and underground gaps.

If you cannot stand the transformation sprites, hiding the accessory removes the visuals and leaves the effects running.