Mockingbird, Ace AgentHow it works & interactions with other cards

Double Strike and Counter Mechanics

Mockingbird, Ace Agent possesses Double strike, meaning it deals both first-strike and regular combat damage. Its triggered ability activates 'Whenever you cast a spell that targets a creature you control.' This triggers during the casting process, meaning the +1/+1 counter is placed on Mockingbird before the targeting spell even resolves. Note that the spell only needs to target at least one creature you control; it doesn't matter if it also targets opponents' permanents or multiple creatures.

Step-by-Step Resolution

When you cast a spell, you first announce it and put it on the stack, then choose targets. If at least one of those targets is a creature you control, Mockingbird's ability triggers and goes on the stack above your spell. The ability resolves first, granting Mockingbird a +1/+1 counter. Finally, your original spell resolves. If your spell is countered, Mockingbird still keeps the counter because the ability triggers upon the act of casting, not resolution.

Common Pitfalls to Avoid

A common mistake is thinking Mockingbird triggers on abilities. It only triggers on 'spells,' so activated or triggered abilities that target your creatures will not grant a counter. Additionally, the spell must be 'cast.' Copying a spell on the stack usually does not count as casting unless the effect specifically says to 'cast the copy.' Finally, remember that Mockingbird can target itself with a spell to trigger its own growth ability.

Tactical Timing

To maximize Mockingbird's potential, use instant-speed combat tricks. Because Mockingbird has Double strike, increasing its power before the first combat damage step effectively doubles the value of every counter it has received. It is often best to hold your targeting spells for the declare blockers step to surprise your opponent with sudden lethal damage.

Interaction examples

Scaling with Utility

Solemn Simulacrum

If you cast a spell like 'Ephemerate' targeting your Solemn Simulacrum to blink it for lands, Mockingbird, Ace Agent will trigger. You will put a +1/+1 counter on Mockingbird, and then the spell will resolve, letting you search for a land with the Golem's enter-the-battlefield ability.

Doubling the Growth

Roaming Throne

If Roaming Throne enters the battlefield and you choose 'Human', 'Spy', or 'Hero', its replacement effect applies. When you cast a spell targeting a creature you control, Mockingbird's ability triggers. Because of Roaming Throne, it triggers an additional time, resulting in two +1/+1 counters being placed on Mockingbird instead of one.

Self-Buffing for Lethal

If you cast an Aura or a pump spell directly on Mockingbird, Ace Agent, it targets itself. The trigger goes on the stack and resolves, giving it a +1/+1 counter. Then the spell resolves, adding even more stats. With Double strike, these combined bonuses are applied twice during combat.