In the City of Haze, in the room across from the Bakery, there is a room with the Skull Bartender. Instead of killing him, stand at the end of the bar for a few seconds until he mixes a drink and slides it at you. The following is a list of all the drinks followed by their effects:
Short Blue Glass
Damage (exact amount unknown). For example, you will take 150 damage on Axe Armor at level 20.