Guise of Fire

A toughness penalty does the quiet work here: stick this on an opposing X/1 and the creature dies before the combat clause ever matters, a removal spell wearing an Aura's clothes for the price of one mana. On anything sturdier, the compulsion takes over: the enchanted creature attacks each combat if able, pulled out from behind blocking duty into a swing you can plan around. That coercion is the real prize against control-leaning bodies, turning a defensive piece into a liability that walks into your removal or your waiting blockers. The "if able" clause is where the trick has limits, though: a creature with defender simply cannot attack, so a true wall shrugs the compulsion off entirely; this only works on creatures that can swing but would rather not. The cost is that you have spent a card to script someone else's combat step, and a sacrifice outlet, a bounce, or a chump block can blunt the plan. It belongs to the lineage of effects that punish creatures for existing rather than answering them cleanly, the edict-and-coerce logic of black recast in red: cheap, conditional, reliant on the opponent fielding a target shaped the right way. The buff-or-curse split depends entirely on what you choose to enchant, the small swingy decision a one-mana Aura is built to create.