Stunning Strike

Flash on an Aura is the whole trick here, and it changes what this piece of removal actually removes. Cast at instant speed in response to an attack or block, it taps the enchanted creature and pulls it out of combat entirely, so it functions as a Fog aimed at a single threat rather than a slow enchantment you have to commit on your own turn. What it leaves behind is the interesting part: a permanent lock rather than a one-turn tempo hit. The creature never untaps for its controller, so it stays frozen indefinitely, doing nothing on defense or offense, until someone bounces or destroys the Aura. That is a soft answer to a big body that blue rarely gets to play, and it dodges the graveyard entirely, which matters against recursion. The design leaves a deliberate escape hatch: legendary creatures untap normally, so the lock only holds down the rank and file. Against a commander or a marquee legend you get the combat blowout and nothing more, while ordinary threats stay pinned. It is a blue answer built around blue's instincts: don't kill the thing, just make sure it never does anything useful again, and hold the interaction open until the moment it hurts most.