Unifier of Realms

Unifier of Realms's power and toughness are each equal to the greatest mana value among artifacts you control.

At the beginning of your upkeep, add {c} for each artifact you control. This mana can’t be spent to cast nonartifact spells. Until end of turn, you don’t lose this
mana as steps and phases end.

At these points, Physical matter, Cognitive thought, and Spiritual essence become one--and a being can slide between Realms.

based on Karn, Legacy Reforged