Higure, the Still Wind

Ninjutsu's whole conceit is the bait-and-switch in combat: during the attack step, before damage, you return an unblocked attacker to hand and drop a ninja in its place, tapped and already swinging. This is the legend the mechanic was built to reward going wide on. Once the ninja connects, the combat damage trigger fetches another Ninja straight to your hand, so each successful swing refills the resource it just spent, turning one unblocked attacker into a self-sustaining ninjutsu engine. The separate activation closes the loop from the other end: pay it and a target Ninja can't be blocked this turn, manufacturing the unblocked body that ninjutsu needs and setting up the next damage trigger and the next tutor. That tutor finds only Ninja cards, which is the constraint doing the design work; it makes the legend the centerpiece of a tribe rather than a generically efficient blue body, and the chain only spins for a deck deep enough in ninjas to keep feeding it. The 3/4 frame matters more than it reads: it survives the spot removal and chump-block math a fragile beater would lose to, buying the engine the turns it needs to spin. As tribal payoffs go, this is the one that bundles card advantage, a tutor, and (across two abilities) the evasion to keep landing hits, and it remains the card the Ninja archetype is built around when it wants an engine rather than a finisher.