Celestial Archon

Bestow is an alternative cost to cast the spell with bestow. It can't be combined with other alternative costs, such as casting a spell "without paying its mana cost."

2018-07-13

If a permanent with bestow enters the battlefield by any method other than being cast, it will be an enchantment creature. You can't choose to pay the bestow cost and have it become an Aura.

2018-07-13

Unlike other Aura spells, an Aura spell with bestow still resolves if its target is illegal. Instead of entering the battlefield as an Aura, the effect making it an Aura spell ends, it loses enchant creature, and it resolves and enters the battlefield as an enchantment creature.

2018-07-13

Unlike other Auras, an Aura with bestow isn't put into its owner's graveyard if the enchanted creature leaves the battlefield or becomes an illegal creature for the Aura to enchant. Rather, the effect making it an Aura ends, it loses enchant creature, and it remains on the battlefield as an enchantment creature. It can attack (and its abilities can be activated, if it has any) on the turn it becomes unattached if it's been under your control continuously, even as an Aura, since your most recent turn began.

2018-07-13