Sigardian Zealot

The condition is the design puzzle here: not just "choose any number of creatures," but any number of creatures with different powers. That clause turns the anthem into a tax on homogeneity. A wide board of identical 1/1s picks up exactly one recipient; a stratified board of a 1/1, a 2/2, and a 4/4 pumps all three. The reward structure quietly pushes against the go-wide instinct most green group-pump cards encourage, and toward a spread of creature sizes that a typical aggressive board does not naturally produce. Because X scales off this creature's own power, the size of the buff is baked into how large a body you can protect and grow the Zealot into: pump effects, counters, and its own +X/+X from another source all feed a bigger fan-out. The buff lasts only until end of turn, so nothing compounds across combats; the trigger fires at the beginning of combat on your turn and asks the same question again from scratch. Vigilance is the tell for how the effect wants to be spent, keeping the pumped attackers back to block while still committing to the swing. The 3/3 body for five mana is deliberately unthreatening on its own; the value lives entirely in what stands beside it, and in whether you built a board diverse enough to unlock the fan-out. It rewards a deckbuilder who thinks about the distribution of power across a battlefield rather than the raw count of bodies on it.