Darksteel Citadel

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Blasted Landscape

{T}: Add {C}.
Cycling {2} ({2}, Discard this card: Draw a card.)

D00-DL, Caricaturist

When D00-DL, Caricaturist enters, create a 4/4 colorless Sketch creature token, which you have fifteen seconds to draw. The token has flying if it has wings in its art. The same is true for first strike and a sword, vigilance and a shield, menace and mean eyes, trample and horns, deathtouch and claws, lifelink and fangs, and haste and footwear.

Shrine of the Forsaken Gods

{T}: Add {C}.
{T}: Add {C}{C}. Spend this mana only to cast colorless spells. Activate only if you control seven or more lands.

Sanctum of Eternity

{T}: Add {C}.
{2}, {T}: Return target commander you own from the battlefield to your hand. Activate only during your turn.

Bonders' Enclave

{T}: Add {C}.
{3}, {T}: Draw a card. Activate only if you control a creature with power 4 or greater.

Command Beacon

{T}: Add {C}.
{T}, Sacrifice Command Beacon: Put your commander into your hand from the command zone.

Arch of Orazca

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
{T}: Add {C}.
{5}, {T}: Draw a card. Activate only if you have the city's blessing.

Mirrorpool

Mirrorpool enters tapped.
{T}: Add {C}.
{2}{C}, {T}, Sacrifice Mirrorpool: Copy target instant or sorcery spell you control. You may choose new targets for the copy.
{4}{C}, {T}, Sacrifice Mirrorpool: Create a token that's a copy of target creature you control.