Arcane Signet

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

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Buried Ruin: Return target artifact card from your graveyard to your hand.

Shipwreck Marsh

Shipwreck Marsh enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Command Tower

Sol Ring

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Thought Vessel

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Island

Strionic Resonator

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

Tasha, the Witch Queen

Whenever you cast a spell you don't own, create a 3/3 black Demon creature token.
+1: Draw a card. For each opponent, exile up to one target instant or sorcery card from that player's graveyard and put a page counter on it.
−3: You may cast a spell from among cards in exile with page counters on them without paying its mana cost.
Tasha, the Witch Queen can be your commander.

Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters tapped unless you control two or more basic lands.

Fellwar Stone

Displacer Kitten

Avoidance — Whenever you cast a noncreature spell, exile up to one target nonland permanent you control, then return that card to the battlefield under its owner's control.