Sandsteppe Citadel

Sandsteppe Citadel enters tapped.
{T}: Add {W}, {B}, or {G}.

Eerie Ultimatum

Return any number of permanent cards with different names from your graveyard to the battlefield.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Mythos of Nethroi

Destroy target nonland permanent if it's a creature or if {G}{W} was spent to cast this spell.

Indatha Triome

({T}: Add {W}, {B}, or {G}.)
Indatha Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Nethroi, Apex of Death

Mutate {4}{G/W}{B}{B} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Deathtouch, lifelink
Whenever this creature mutates, return any number of target creature cards with total power 10 or less from your graveyard to the battlefield.