Soulmates 
Enchantment — Aura
Enchant two creatures Enchanted creatures each get +1/+1 and have hexproof. When one of the enchanted creatures dies, destroy the other.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyNOT LEGALvintageNOT LEGALcommanderNOT LEGAL