Haze Frog

A Fog wearing a body. The whole tradition of green's combat-blanking spells, from the original Fog onward, has been about timing the answer to land in the right combat step for a single mana; the trade here is that you pay five and get a 2/1 that sticks around afterward. Flash is what makes the rate defensible: cast it during your opponent's declare-attackers step and the entry trigger wipes out all combat damage other creatures would deal, then the Frog is parked on the board as a chump or an attacker on your following turn rather than a one-shot spell gone to the graveyard. The clause is broader than a one-sided fog, too: it prevents damage from your other creatures as well, so this is purely a defensive reset, not a way to push through unblocked. The design tension is the obvious one, that a five-mana flash creature is a steep price for an effect a one-mana instant has covered since the game's earliest days, but it answers a different question. A Fog protects you once and is gone; this leaves a permanent on the field, which matters when the body, however small, is the point of holding up mana in the first place.