Wrenn and Realmbreaker

Lands you control have "{T}: Add one mana of any color."
[+1]: Up to one target land you control becomes a 3/3 Elemental creature with vigilance, hexproof, and haste until your next turn. It's still a land.
[−2]: Mill three cards. You may put a permanent card from among the milled cards into your hand.
[−7]: You get an emblem with "You may play lands and cast permanent spells from your graveyard."

March of the Machine Promos

March of the Machine

Lands you control have "{T}: Add one mana of any color."
+1: Up to one target land you control becomes a 3/3 Elemental creature with vigilance, hexproof, and haste until your next turn. It's still a land.
−2: Mill three cards. You may put a permanent card from among the milled cards into your hand.
−7: You get an emblem with "You may play lands and cast permanent spells from your graveyard."

The lands you play and spells you cast from your graveyard follow the usual timing restrictions, and you must pay any costs for spells you cast.