Seedglaive Mentor

Valiant fires once per turn no matter how many times you point something at this creature, and that single-trigger ceiling is what keeps the mechanic from spiraling in a cheap-spells shell: the reward comes from targeting once, deliberately, rather than dumping a hand of tricks onto the same body in one window. What this Mouse Soldier does with the constraint is fold the payoff into a package that already wants to attack. Vigilance keeps the counter-growing beater available on defense; haste puts it on the clock the turn it lands, before an answer arrives. The trigger only fires when a spell or ability you control targets the creature itself, so the design pulls toward a build stocked with your own targeting effects aimed here: a one-mana pump on this body, an equip or aura going onto it, a spell whose whole job is to touch it. Each of those was doing something already, and the counter is a permanent bonus stapled onto an interaction you were casting anyway. Because the counters accrue across turns rather than in one explosive burst, they suit a modest 3/2 that needs to outgrow the range where a fair trade stops the clock. The small body is deliberate; the counters are what carry it past the point where a straight one-for-one keeps pace. The whole engine leans on discipline: you target it when it matters, not whenever you can.