Ishida, Forgotten Warleader

Double Strike, Hexproof, Trample
Whenever Ishida, Forgotten Warleader attacks,
you may add a strength counter on Ishida,
Forgotten Warleader, then Ishida, Forgotten Warleader gains +X/+X until end of turn
where X is the number of strength counters on Ishida, Forgotten Warleader