Flowstone Strike

The +1/-1 is the tell that this is a Tempest-block design, not a generic pump spell: red of that era used toughness reduction as its removal vocabulary, and stapling it to haste turns one card into either a finisher or an assassin depending on what you point it at. Aim it at your own attacker and the line reads as a small last-point of damage plus the ability to swing the turn the creature lands, a way to convert a freshly cast body into immediate pressure. Aim it at an opposing one-toughness blocker and it functions as removal that doubles as a combat trick, killing the creature before it can absorb an attack. The drawback to the controller is built into the same line that powers it: the -1 makes this a poor pump for anything already low on toughness, so the card rewards committing it to a healthy body or spending it as a kill spell rather than splitting the difference. That dual nature, neither a clean burn spell nor a clean pump, is exactly the friction red instants of this period traded in, before the color settled into the cleaner damage-based removal it favors now.