Magmablood Archaic (Secrets of Strixhaven)

Creature Ñ Avatar - Trample, reach
Converge Ñ This creature enters with a +1/+1 counter on it for each color of mana spent to cast it.
Whenever you cast an instant or sorcery spell, creatures you control get +1/+0 until end of turn for each color of mana spent to cast that spell.