Badberry

Up to ten berries appear in your hand and are infused with necromantic magic for the duration. A creature can use its action to eat up to 3 berries. Eating a berry reduces the eater's hit point maximum by 1d4 for 24 hours, and the berry makes the eater have to eat and drink double their normal amount. These berries appear to be goodberries under every form of non-magical inspection.

The berries lose their potency if they have not been consumed within 24 hours of the casting of this spell.