Ekko

Legend · PassiveEmpower[Empower] — 1 Energy, Exhaust (Use only if not Empowered.) Disempower me, Exhaust: Reduce the cost of the next unit you play this turn by 2 Energy + [C] and give it "Kill me at end of turn."

Ekko bends time. Boy Who Shattered Time makes the next unit you play [2][C] cheaper, and Ekko, Revolutionary rewinds himself — banished and played again, ready — so his trials teach you what to discount, and when to rewind.