Swamp

Command Tower

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

Kroxa, Titan of Death's Hunger

When Kroxa enters, sacrifice it unless it escaped.
Whenever Kroxa enters or attacks, each opponent discards a card, then each opponent who didn't discard a nonland card this way loses 3 life.
Escape—{B}{B}{R}{R}, Exile five other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

Mountain

Arcane Signet

Mesmeric Orb

Whenever a permanent becomes untapped, that permanent's controller mills a card.