Ironshell Beetle

A one-time growth spurt that survives the turn it was cast on. Where a combat trick pumps for a single attack and then evaporates, this body parks a permanent +1/+1 counter wherever it does the most good and leaves it there. The arithmetic is modest: a 1/1 that hands off its counter for two total power split across two bodies, or a 2/2 if you name the Beetle itself and keep the bonus on the creature that carried it in. You get exactly one counter, so the placement choice is the whole interaction: grow a fragile attacker into trade-favorable range, or settle for a serviceable two-drop. The quiet upside of distributing stats this way is that the bonus is independent of its source. Once the counter lands on a second creature, the Beetle can die, chump, or trade without touching the stats it dispensed; the body is incidental the moment the trigger resolves. The catch runs the other direction, of course: target the creature you most want to grow, and removal pointed at that target takes the counter down with it before it ever sticks. This is filler in the honest sense, an enabler for green decks that want bodies on the board and a small nudge to combat math, and it asks nothing beyond having a second creature worth nudging.