Elori, the Living Arc

Bestow {1}{r}{r}{r}
Whenever Elori becomes attached to a creature,
Elori deals 3 damage to it. If Elori would become unattached from a creature, you may attach Elori
to another creature instead.
Double strike
Enchanted creature gets +3/+0 and has double
strike.
When Elori enters the battlefield as a creature or
is no longer bestowed, it deals 3 damage to each opponent.