Brass's Bounty

For each land you control, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Rapacious Dragon

Flying
When this creature enters, create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Koth of the Hammer

+1: Untap target Mountain. It becomes a 4/4 red Elemental creature until end of turn. It's still a land.
−2: Add {R} for each Mountain you control.
−5: You get an emblem with "Mountains you control have '{T}: This land deals 1 damage to any target.'"

Tunneling Geopede

Landfall — Whenever a land you control enters, Tunneling Geopede deals 1 damage to each opponent.

Maraxus of Keld

Maraxus of Keld's power and toughness are each equal to the number of untapped artifacts, creatures, and lands you control.

Spitfire Lagac

Landfall — Whenever a land you control enters, this creature deals 1 damage to each opponent.

Rionya, Fire Dancer

At the beginning of combat on your turn, create X tokens that are copies of another target creature you control, where X is one plus the number of instant and sorcery spells you've cast this turn. They gain haste. Exile them at the beginning of the next end step.