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.

Consecrate Land

Enchant land
Enchanted land has indestructible and can't be enchanted by other Auras.

Chamber of Manipulation

Enchant land
Enchanted land has "{T}, Discard a card: Gain control of target creature until end of turn."

Equinox

Enchant land
Enchanted land has "{T}: Counter target spell if it would destroy a land you control."

Ossification

Enchant basic land you control
When this Aura enters, exile target creature or planeswalker an opponent controls until this Aura leaves the battlefield.

Sunken Field

Enchant land
Enchanted land has "{T}: Counter target spell unless its controller pays {1}."