Feral Invocation

The flash is the entire argument. A flat +2/+2 aura stapled to a creature is some of the oldest, dullest arithmetic in the game; Unholy Strength did the same math in the other direction long before, and nobody built decks around it. What flash buys is the timing window: instead of committing the buff face-up on your own turn and inviting a removal spell in response, you hold it until combat resolves the way it pleases you. Leave the three mana up, let an attacker walk into a block, then ambush the trade by adding four points of stats at instant speed. The opponent who counted toughness wrong loses the creature; the one who suspects an open hand of green mana might hide a trick attacks more cautiously and gets less out of the turn. That is the auras-as-combat-trick lineage, the small family of pump enchantments that earn a slot by pretending to be Giant Growth while leaving a permanent on the board after the exchange. The cost of the disguise is real: it is still an Aura, so it still hands a two-for-one to any removal that answers the host, and the body it sits on has to survive to matter. But the choice of when to reveal it, rather than what it does, is where the card's value lives, and it is the difference between a buff nobody respects and a buff that has to be played around.