Hedronbinder Seraph

Flying
Alignment (As long as you control three or more
Hedron tokens, they are aligned)
Whenever Hedronbinder Seraph or another
creature with flying enters the battlefield under
your control, create a colorless Hedron artifact
token with "{2}, {t}: Scry 1." Then if Hedrons you
control are aligned, you may sacrifice three
Hedrons. If you do, exile target creature.