March of the Machine

Polukranos Reborn // Polukranos, Engine of Ruin | Legendary Creature // Legendary Creature | Hydra // Phyrexian Hydra | Reach {6}{W/P}: Transform Polukranos Reborn. Activate only as a sorcery. ({W/P} can be paid with either {W} or 2 life.) // Reach, lifelink Whenever Polukranos, Engine of Ruin or another nontoken Hydra you control dies, create a 3/3 green and white Phyrexian Hydra creature token with reach and a 3/3 green and white Phyrexian Hydra creature token with lifelink. | David Auden Nash

Ghalta and Mavren | Legendary Creature | Dinosaur Vampire | Trample Whenever you attack, choose one — • Create a tapped and attacking X/X green Dinosaur creature token with trample, where X is the greatest power among other attacking creatures. • Create X 1/1 white Vampire creature tokens with lifelink, where X is the number of other attacking creatures. | Zezhou Chen

Invasion of Alara | Battle | Siege | When Invasion of Alara enters the battlefield, exile cards from the top of your library until you exile two nonland cards with mana value 4 or less. You may cast one of those two cards without paying its mana cost. Put one of them into your hand. Then put the other cards exiled this way on the bottom of your library in a random order. | Mathias Kollros

Omnath, Locus of All | Legendary Creature | Phyrexian Elemental | If you would lose unspent mana, that mana becomes black instead. At the beginning of your precombat main phase, look at the top card of your library. You may reveal that card if it has three or more colored mana symbols in its mana cost. If you do, add three mana in any combination of its colors and put it into your hand. If you don't reveal it, put it into your hand. | Bryan Sola