Sovereigns of Lost Alara

Sovereigns of Lost Alara

Creature - Spirit | Power/Toughness: 4 / 5 (CMC 6)
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever a creature you control attacks alone, you may search your library for an Aura card that could enchant that creature, put it onto the battlefield attached to that creature, then shuffle.