Canopy Dragon

The whole card is a toggle between two evasion modes, paid for one combat step at a time. The default is a trampling ground beater that pushes damage past chump blockers. The activated ability swaps that for flying, and the friction is what makes the design work: it costs mana every time, the flying lapses by your next turn, and the moment it takes to the air it surrenders trample. You only ever hold one evasion mode at once, and you pay each combat to decide which one the blockers in front of you call for. Against a wall of small ground creatures, trample is the answer; against a defense with nothing to contest the air, paying to fly opens a lane a stalled board could not find otherwise. The per-turn tax is the leash on the whole thing: it never gets both keywords stapled on for free, so the value is in the read rather than the rate. That fits a green creature renting air access it does not own outright, an instinct the era leaned on when it wanted big green bodies to borrow abilities other colors got as a birthright. The cost of switching is precisely what stops a six-mana 4/4 from quietly outclassing a plain flier of the same size.