Instantáneo
Fortalece 1, luego pon un contador +1/+1 sobre cada criatura que controlas con un contador +1/+1 sobre ella. (Para fortalecer 1, elige la criatura con menor resistencia entre las criaturas que controlas y pon un contador +1/+1 sobre ella.)
You determine which creature to put counters on as the spell or ability that instructs you to bolster resolves. That could be the creature with the bolster ability, if it's still under your control and has the least toughness.