The Brothers' War

Autonomous Assembler | Artifact Creature | Assembly-Worker | Prototype {1}{W} — 2/2 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.) Vigilance {1}, {T}: Put a +1/+1 counter on target Assembly-Worker you control. | Slawomir Maniak

Steel Seraph | Artifact Creature | Angel | Prototype {1}{W}{W} — 3/3 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.) Flying At the beginning of combat on your turn, target creature you control gains your choice of flying, vigilance, or lifelink until end of turn. | Denys Tsiperko

Terisian Mindbreaker | Artifact Creature | Juggernaut | Whenever Terisian Mindbreaker attacks, defending player mills half their library, rounded up. Unearth {1}{U}{U}{U} ({1}{U}{U}{U}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.) | Steve Prescott

Razorlash Transmogrant | Artifact Creature | Zombie | Razorlash Transmogrant can't block. {4}{B}{B}: Return Razorlash Transmogrant from your graveyard to the battlefield with a +1/+1 counter on it. This ability costs {4} less to activate if an opponent controls four or more nonbasic lands. | Kekai Kotaki

Transmogrant's Crown | Artifact | Equipment | Equipped creature gets +2/+0. Whenever equipped creature dies, draw a card. Equip {2} or {B} | Nino Vecia

Perennial Behemoth | Artifact Creature | Beast | You may play lands from your graveyard. Unearth {G}{G} ({G}{G}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.) | Wayne Reynolds

Simian Simulacrum | Artifact Creature | Ape | When Simian Simulacrum enters the battlefield, put two +1/+1 counters on target creature you control. Unearth {2}{G}{G} ({2}{G}{G}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.) | Randy Vargas

Liberator, Urza's Battlethopter | Legendary Artifact Creature | Thopter | Flash Flying You may cast colorless spells and artifact spells as though they had flash. Whenever you cast a spell, if the amount of mana spent to cast that spell is greater than Liberator, Urza's Battlethopter's power, put a +1/+1 counter on Liberator. | Ekaterina Burmak

The Stasis Coffin | Legendary Artifact | | {2}, {T}, Exile The Stasis Coffin: You gain protection from everything until your next turn. | Artur Nakhodkin

The Stone Brain | Legendary Artifact | | {2}, {T}, Exile The Stone Brain: Choose a card name. Search target opponent's graveyard, hand, and library for up to four cards with that name and exile them. That player shuffles, then draws a card for each card exiled from their hand this way. Activate only as a sorcery. | Irina Nordsol

Thran Spider | Artifact Creature | Spider | Reach When Thran Spider enters the battlefield, you and target opponent each create a tapped Powerstone token. {7}: Look at the top four cards of your library. You may reveal an artifact card from among them and put it into your hand. Put the rest on the bottom of your library in a random order. | Joshua Cairos

Terror Ballista | Artifact Creature | Construct | Menace Whenever Terror Ballista attacks, you may sacrifice another creature. When you do, destroy target creature an opponent controls. Unearth {3}{B}{B} ({3}{B}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.) | Leon Tukker

Artificer's Dragon | Artifact Creature | Dragon | Flying {R}: Artifact creatures you control get +1/+0 until end of turn. Unearth {3}{R}{R} ({3}{R}{R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.) | Leon Tukker

Woodcaller Automaton | Artifact Creature | Construct | Prototype {2}{G}{G} — 3/3 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.) When Woodcaller Automaton enters the battlefield, if you cast it, untap target land you control. It becomes a Treefolk creature with haste and base power and toughness equal to Woodcaller Automaton's power and toughness. It's still a land. | Ryan Pancoast

Phyrexian Dragon Engine | Artifact Creature | Phyrexian Dragon | Double strike When Phyrexian Dragon Engine enters the battlefield from your graveyard, you may discard your hand. If you do, draw three cards. Unearth {3}{R}{R} (Melds with Mishra, Claimed by Gix.) | Chris Rahn

The Mightstone and Weakstone | Legendary Artifact | Powerstone | When The Mightstone and Weakstone enters the battlefield, choose one — • Draw two cards. • Target creature gets -5/-5 until end of turn. {T}: Add {C}{C}. This mana can't be spent to cast nonartifact spells. (Melds with Urza, Lord Protector.) | Ryan Pancoast