Estrid, the Masked

[+2]: Untap each enchanted permanent you control.
[−1]: Create a white Aura enchantment token named Mask attached to another target permanent. The token has enchant permanent and umbra armor.
[−7]: Mill seven cards. Return all non-Aura enchantment cards from your graveyard to the battlefield, then do the same for Aura cards.
Estrid, the Masked can be your commander.