Arcbound Slasher

Two counter-based keywords rarely share a card, and the pairing here produces a genuine fork rather than a pile of stats. Modular delivers four +1/+1 counters on entry and promises they will not be wasted: when the creature dies, they scatter to another artifact creature, so death is a transfer rather than a loss. Riot then hands you a fifth counter or, instead, haste. That is the decision. Bank the extra counter and you have a heavier body whose whole payload will migrate down the artifact chain when it falls, exactly the slow-value plan a modular deck wants. Take haste and the four counters swing the turn they arrive, converting a five-mana entry into an immediate threat that still bequeaths its counters later. The cleverness lives in that second line: haste usually rewards a creature you plan to keep around, but here the counters outlive the body, so an aggressive attack loses nothing even when it trades in combat. The printed 0/0 makes the intent plain. This is a counter-delivery vessel that borrows just enough of a body to attack, and Riot simply decides whether the counters land with speed or with mass.