The second clause is the whole card, and the Ninja density is what activates it. The free attach triggers on any Ninja entering the battlefield, however it arrives, and this set is built to keep that valve open: Foot Ninjas, Mechanized Ninja Cavalry, and a stack of hybrid and white legends that slide onto a clear board through Sneak. That count is what makes the equip-two tax irrelevant most games. Without it, you are paying one mana plus equip to suit up a small body in a format where Stomped by the Foot answers the carrier at instant speed and Grounded for Life gets cheaper the moment you tap that body to attack.
With it, you get the rare one-drop that scales into the midgame. Drop it turn one, land a Ninja turn three or four, connect, untap, and the same body now holds the ground on the crack-back. The untap clause is what earns the slot: it converts a single hit into two-way pressure in a format that grinds through combat math rather than racing the clock.
WB Ninjas wants it most, since that pair already leans on small evasive bodies and needs a way to turn lone hits into a recurring threat. Take it P2P4 to P2P6 there, maindeck. RW Equipment values it lower: that deck would rather have Bespoke Bō's raw size than a re-attach keyed to a creature type it barely fields, so the Katana falls to a P3 hold. The clear failure case is white drifting toward fliers, where the buff is fine but the free-attach trigger almost never fires and you pay full equip on a card that does nothing the turn it lands. Strip out the Ninjas and this is a 15th pick.
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