Minthara, Merciless Soul (Commander Legends: Battle for Baldur's Gate)

Legendary Creature Ñ Elf Cleric - Minthara has ward {X}, where X is the number of experience counters you have.
At the beginning of your end step, if a permanent you controlled left the battlefield this turn, you get an experience counter.
Creatures you control get +1/+0 for each experience counter you have.