March of the Machine

Halo Hopper | Artifact Creature | Frog | Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) | Daniel Ljunggren

Phyrexian Archivist | Artifact Creature | Phyrexian Construct | Reach {2}, {T}: Put target card from a graveyard on the bottom of its owner's library. | Daniel Romanovsky

Skittering Surveyor | Artifact Creature | Construct | When Skittering Surveyor enters the battlefield, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle. | Igor Kieryluk

Invasion of Ravnica // Guildpact Paragon | Battle // Artifact Creature | Siege // Construct | (As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.) When Invasion of Ravnica enters, exile target nonland permanent an opponent controls that isn't exactly two colors. // Whenever you cast a spell that's exactly two colors, look at the top six cards of your library. You may reveal a card that's exactly two colors from among them and put it into your hand. Put the rest on the bottom of your library in a random order. | Leon Tukker