Pyrophobia

A three-damage sorcery for two mana is unremarkable rate; the second line is the whole joke. Cowards can't block this turn keys off a creature type printed on a small handful of red and black creatures, most of them scared-looking goblins and skeletons drawn to be exactly as cowardly as they act. The design is pure flavor engineering: the removal half kills most targets outright, and the "can't block" rider is dead text at nearly every table, since the number of cards actually printed as Cowards is a rounding error. That is the point. It is a joke first and a spell second, built so the mechanical payload works whether or not the punchline ever lands. The lineage here is the recurring Magic tradition of stapling a literal keyword to a creature type nobody plays, then rewarding it with a rules effect that reads as comedy: the card cares about fear, the creatures are named for cowardice, and the interaction is setup and punchline at once. Strip the second sentence and you have a slightly overcosted burn spell that happens to only hit creatures; keep it and you have a design where the joke is the reason the card exists, with the removal as the delivery vehicle.