Brightfield Mustang

The Saddle keyword taxes your board before combat: you tap other creatures at sorcery speed to arm the Mount, and Saddle 1 sets that price at a single point of power, so one spare token or dork suffices. What separates this design from the rest of the mechanic is the trigger's timing. It fires on the attack declaration, not on damage, and the instant it swings while saddled it untaps itself and takes a +1/+1 counter. That self-untap is the load-bearing wrinkle. Most attackers spend their tap to swing and sit exposed to the crackback; this one comes home ready to block or trade, so the growth is not just a faster clock but a defensive posture the counters keep raising. Because the counter lands whether or not the attack connects, the snowball does not depend on getting through: a saddled swing into a wall still nets a permanent point of power and an untapped body. The catch lives in Saddle's one-turn duration. Every attack you want the trigger for demands re-saddling, and the creature you tapped to arm it stays tapped: the Mustang untaps, its handler does not. The whole shape is deliberate, a white beater built to compound through combat under its own power, using an attack-step untap to sidestep the vulnerability window that usually punishes committing, provided you keep feeding it warm bodies to saddle with.