Ellirnia Mistbourn

Vigilance, partner.
Whenever Ellirnia enters the battlefield you become the monarch.
The monarch must attack each turn if able.
Whenever the monarch changes put a +1/+1 counter in Ellirnia.
Remove {x} +1/+1 counters from Ellirnia:
You may cast a card exiled with Xeania with converted mana cost {x} or less without paying
its mana cost.