Arbor Colossus

Reach is the floor here; the activated ability is the whole pitch. A 6/6 with reach already pulls double duty against ground beaters and the air, but spending the monstrosity cost converts that defensive posture into a one-sided answer: the creature grows by three counters and, on the way up, removes a flier an opponent controls. The design ties a stat bump to targeted removal so that the same activation does two jobs, and the wording keeps it honest in two ways. The destroy trigger only fires the first time monstrosity resolves, so this is a single shot of removal, not a repeatable cannon; and it can only hit a creature with flying that an opponent controls, so it answers exactly the threat the reach body is built to block rather than functioning as open-ended interaction. That makes it a green creature that can clear the sky without bending off-color into white or black removal, a recurring tension for the color that big-mana ramp shells have always had to solve through bodies rather than spells. The price is patience: nothing happens the turn it lands, and the monstrosity cost is steep enough that the removal arrives a turn or more after the threat does. It rewards a board state where you can afford to sit behind the reach blocker first and pull the trigger when an evasive creature finally commits.