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Vigilance (Attacking doesn't cause this creature to tap.)
Whenever you attack with three or more creatures, put a +1/+1 counter on target creature you control.
It doesn't matter what happens to the creatures you attacked with once Armasaur Guide's last ability has triggered. When that ability resolves, you'll put a +1/+1 counter on the target creature regardless of whether the creatures you attacked with (or Armasaur Guide) are still on the battlefield.
