Vow of Lightning

Handing an opponent's creature +2/+2 and first strike is the kind of generosity that gets you killed in a multiplayer game: an ordinary Aura does nothing to stop the gift from swinging back into your own board next turn. This one writes the diplomacy into the rules text. The stat boost and first strike are a genuine present, but the enchanted creature cannot turn its blade against you or the planeswalkers you control while the Aura stays attached: a continuous static restriction, not a one-turn handshake. That permanence is the political math. You can drop the upgrade on an ally's blocker or attacker, point its sharpened offense at the table's shared threat, and never worry that the knife comes home to your throat or your loyalty counters. The first-strike grant does the quiet structural work: a vowed creature becomes both a sturdier wall and a more frightening attacker into the other seats, so every added point of power and combat reach is aimed away from your position. It belongs to a five-card cycle of mono-colored Vows, each pairing the identical non-aggression clause with a color-flavored keyword (first strike being red's contribution), all built for the free-for-all table where a buff only counts as generous if it physically cannot turn around and bite the hand that cast it.