Parasitic Bond

Here's a removal spell that pointedly refuses to remove anything. Stick this on an opponent's creature and the creature stays exactly where it is, fully functional, still attacking and blocking, while its controller eats two damage every upkeep for as long as the Aura sticks around. The friction is deliberate: it targets the creature but punishes the player, so the obvious counterplay (sacrificing or bouncing the enchanted creature) means the opponent has to spend resources to cut off a clock you installed for four mana. The result is less a piece of interaction than a slow, self-perpetuating burn engine wearing an Aura's clothing, a design that asks the opponent which they'd rather keep: the creature, or four life every two turns. The trouble is the speed. Two damage a turn is a leisurely pace in a world full of cheaper, faster reach, and the body it's anchored to still does whatever it was doing before. The card reads as a black answer to the red "deal damage over time" enchantment school, but routed through the very creature it declines to kill, which is a strange and slightly self-defeating place to put your inevitability. It's an idea that wants the opponent's own board to be the delivery mechanism for their loss, executed at a rate too gentle to make the threat land.