Phytoburst

Two mana for +5/+5 is a steep number on the green pump curve, well past the modest +3/+3 you usually pay this little for, and the size is the whole transaction: no trample, no protection, no draw, no second mode. Where Giant Growth turns a blocker into a threat, this turns a threat into a finisher, adding five points of damage to a single attacker in one swing. The cost of that ceiling is total commitment along two axes. First, the magnitude: a pump this large lives and dies on the creature surviving to connect, so spot removal in response trades one card for two and a tempo crater, and a chump block reduces the splashiest spell in the deck to nothing. Second, the speed: this is a sorcery, not an instant, so it cannot be held up as a combat surprise or a blowout during the opponent's attack. You commit it on your own turn, telegraphed, before damage is even on the table. That sorcery clause is the real tax on the rate. Strip away the ability to ambush and the +5/+5 stops being a trick and becomes a planned reach effect: a way for a deck that wants one big undercosted swing to overcommit a single body past the point of efficient answers. It is the green pump archetype taken to an extreme, maximum stats for minimum mana, with every other consideration stripped out and handed back to the opponent as a window to respond.