If Spearow has less than 4 damage counters can I use its "Roost" attack?
Yes. You do as much as you can to perform the effect of the attack; in this case remove all the damage counters.
Roost



x2
-20
RoostRemove 4 damage counters from Spearow. Spearow can't retreat during your next turn.
FlapIf Spearow has less than 4 damage counters can I use its "Roost" attack?
Yes. You do as much as you can to perform the effect of the attack; in this case remove all the damage counters.