Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Arcane Signet

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

Muldrotha, the Gravetide

During each of your turns, you may play a land and cast a permanent spell of each permanent type from your graveyard. (If a card has multiple permanent types, choose one as you play it.)

Command Tower

Opulent Palace

Opulent Palace enters tapped.
{T}: Add {B}, {G}, or {U}.

Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.