Silent Arbiter

No more than one creature can attack each combat.
No more than one creature can block each combat.

Windborn Muse

Flying
Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Have

Voice of Victory

Mobilize 2 (Whenever this creature attacks, create two tapped and attacking 1/1 red Warrior creature tokens. Sacrifice them at the beginning of the next end step.)
Your opponents can't cast spells during your turn.

Absolute Virtue

This spell can't be countered.
Flying
You have protection from each of your opponents. (You can't be dealt damage, enchanted, or targeted by anything controlled by your opponents.)

Ghostly Prison

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Mother of Runes

{T}: Target creature you control gains protection from the color of your choice until end of turn.

Bastion Protector

Commander creatures you control get +2/+2 and have indestructible.

Grand Arbiter Augustin IV

White spells you cast cost {1} less to cast.
Blue spells you cast cost {1} less to cast.
Spells your opponents cast cost {1} more to cast.