Armor of Aura

Convoke
Each time enchanted creature takes damage, deal
1 damage to all enemy creatures. This can only
occur once before your next upkeep.
Aura is what fuels are abilities, but beside that, Aura naturally protects our bodies from injury. Some beings prefer to expend Aura to strengthen this natural
"armor", making them very difficult to defeat. Once
I've seen someone's armor react to damage and
outburst harmful energies.