Simplicity's Strength is a Legendary Gem in Diablo III. It can only be socketed into Amulets and Rings, and drops from Greater Rift Guardians. This gem increases damage done with all Primary skills of any class, stacking with other enhancements: damage increase is multiplicative with most similar effects. This includes Signature Spells of Wizards and Witch Doctors. Upgrading increases the damage bonus. This gem has no effect on pets and minions: i.e. Poison Darts cast with Carnevil will not be affected neither by the damage boost nor healing.