Skanos, Dragon Vassal 
Legendary Creature — Dragon Ranger
Specialize
Whenever Skanos, Dragon Vassal attacks, another target attacking creature gets +X/+0 until end of turn, where X is Skanos's power.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyNOT LEGALvintageNOT LEGALcommanderNOT LEGAL