Runed Halo

Protection from a color, a creature type, or a quality is the usual shape; this names a single card, and that constraint is the entire design. You choose a card name as it enters and lock it permanently: no targeting, no damage, no aura from anything bearing that name. The trick is that protection from a name dodges the standard counterplay. Protection from white can be played around with a colorless removal spell; protection from a specific card cannot be, because the named card can no longer target you, damage you, or enchant you, and there is no second copy of itself that points somewhere else. Against a one-card win condition or a combo piece that has to connect, calling it is a hard wall. The cost of that precision is information: you have to know the threat before it lands, and you commit to a single answer with no take-backs. Name the wrong card and the enchantment sits idle while the actual problem resolves. It is preemptive, surgical hate that asks you to read your opponent's list before they cast the card you fear most. Damage prevention, aura immunity, and target-proofing all bundled under one named string: narrow by construction, but absolute inside the window it covers.