Sunken Citadel

1, T: Scry 1. Put a landmark counter on this artifact. Then if there are three or more landmark counters on it, remove those counters, transform this artifact, and create three Treasure tokens. (They're artifacts with "T, Sacrifice this token: Add one mana of any color.")

At the beginning of your end step, if you descended this turn, create a Treasure token. (You descended if a permanent card was put into your graveyard from anywhere.)

Flying When this creature enters, create a 1/1 colorless Gnome artifact creature token.

T: Add C. 1, T, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Draw three cards, then discard a card.

As this land enters, choose a creature type. T: Add C. T: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

(T: Add U.)

As this land enters, choose a creature type. T: Add C. T: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.