Polarities Mod/The Call of the Moon Lord

The Call of the Moon Lord is a Hardmode, post-Moon Lord book that is purchased from the for  after the Moon Lord is defeated. When used, it grants a 50% chance of lifesteal to all damage dealt by the player, causing them to heal a small fraction of the damage of each attack.

Trivia

 * Its title references the 1928 horror short story The Call of Cthulhu.