Electrostatic Pummeler

Exponential growth, distilled to a single permanent. Each activation reads the creature's current power and doubles it, so a 1/1 becomes 2/2 becomes 4/4 becomes 8/8 with every payment, and the curve steepens the longer you keep feeding it. The constraint is the energy itself: the body arrives with exactly three counters, enough for one pump on its own, which makes it a battery that has to be refilled from elsewhere to chain activations and run the math out to lethal. That dependency is the whole shape of the card. Cut off from a supply line of energy, it is a fragile 1/1 that can swing once for a few extra points; fed a steady stream, it spirals past any blocker the moment it has enough counters banked. Because the multiplier keys off power specifically, anything that raises power before the chain begins gets swept into every subsequent doubling: a +1/+1 counter or a straight power buff turns a 1/1 into a 2/2 that the first activation reads as 2, then 4, then 8, compounding far faster than a raw 1/1 would. Toughness-only pumps and evasion do not enter that math; they keep the creature alive and get it through, which matters, but the number the ability doubles is power alone. The result is a three-mana creature that does almost nothing in a vacuum and threatens to close the game in one combat step the turn the numbers tip over, a ceiling bounded only by how much energy you can produce and how many activations you can squeeze in before the turn ends.