Yggdrasil's Tap

This punch knife stands out from others being made of a dark wood that's harder than iron. You gain a +1 bonus to attack rolls and damage rolls with this magic weapon. When you hit a creature with this weapon, you can roll and expend a Hit Point Die. The target takes extra Piercing damage equal to the roll, and you regain the same number of Hit Points.

Sap (Mastery): If you hit a creature with this weapon, that creature has Disadvantage on its next attack roll before the start of your next turn.

Proficiency: simple, punch knife Source: Ben Huffman - Pugilist (Third Party)