Emergent Woodwurm

The interesting tension here is that Backup was built as a combat-support keyword, a way to shunt some counters and a temporary ability onto a creature you already wanted to swing with, and this design staples that mechanism to an attack trigger that is genuinely worth exporting. The decision it forces sits at the enters-the-battlefield moment. Keep the three counters on the Wurm and it swings as a 7/7, looking seven cards deep for a permanent costing up to seven and dropping it in for free: a self-contained engine that pulls lands, rocks, and fat threats out of the deck every time it attacks. Send the counters to another creature instead and that creature inherits the attack trigger for exactly this turn, while the Wurm itself shrinks back to its printed 4/4 body and its own four-deep, four-cost dig. That is the gamble, and it is a genuine fork rather than a default: the dig depth and the mana-value cap both key off the attacker's power, so where you put the counters decides both how big a permanent you can cheat out and how deep you see. The loop is self-referential, since the power that determines the payoff is the same power the counters inflate. It rewards a board already built to attack rather than trying to assemble one, which is exactly the seam Backup was invented to occupy: not a card that wins on its own, but one that makes an attack you were already committing to pay a dividend it could not before.