Agnaktor

Magma Armor — When Agnaktor enters the battefield, or when you cast an instant or sorcery spell, Agnaktor gains a shield counter. Give it +2/+0 until end of turn.

Boast - Remove a shield counter: Deal 2
damage and Inflict Fireblight on up to {x} target creatures, where {x} is Agnaktor's power.