Krasis Incubation

A neutralizing Aura built around its own undo button. A plain pacifying enchantment sits on a creature forever; this one shuts the target down completely (no attacking, no blocking, and crucially no activated abilities of any kind, which means mana sinks, sacrifice outlets, and tap-effects all go dark too) but bakes in a release valve. Pay the cost, return the Aura to hand, and the creature walks away with two permanent +1/+1 counters. Park it on your own board and you have a growth engine: lock the creature down for a turn, then redeploy the Aura while the counters stay put. Park it on an opponent's threat and the bounce becomes a genuine decision, because letting their creature off the leash with two extra counters can cost you more than leaving the lock in place. Since the activation carries no timing restriction, the unlock can happen at instant speed: free your own enchanted blocker to interpose against an incoming attack, or bank the counters at the moment that matters most. That pull between containment and investment is unusual for a color pair whose interaction usually runs on bounce and tempo rather than handing counters across the table. The activation cost living in the same two colors as the Aura is what keeps it reusable: removal and a counter engine folded into one slot, designed so the answer never wants to stay permanent.