Primal Forcemage

The word doing all the load-bearing work here is "enters," and the +3/+3 lasting only until end of turn is what turns this Elf into a burst weapon rather than an anthem. It rewards the turn you unload a hand of creatures, not the turn you sit on a developed board, because the bonus evaporates and the bodies revert. That makes it a fundamentally different animal from a static pump like Glorious Anthem, which leaves permanent stats behind: those reward presence, this rewards arrival. There is a real catch the rate hides, though: nothing here grants haste. A fresh creature usually cannot convert its temporary bulk into damage the turn it enters, so the bonus most often does its work on defense (a chump that suddenly trades up, a blocker that ambushes an attacker into the dirt) or on creatures that already swing the turn they land. The combat math it warps is the math the opponent thought they had solved when they attacked into an empty-looking board. The design also leans on the word "another," so the Forcemage never pumps itself, keeping it a 2/2 the opponent can profitably kill before the engine compounds. Flood the board with hasty token swarms, blink loops, or reanimation that arrives ready to attack, and the temporary nature stops being a drawback: you only need the creatures big for the one combat step that matters.