The Brothers' War

Rescue Retriever | Creature | Dog Soldier | Flash When Rescue Retriever enters the battlefield, put a +1/+1 counter on each other Soldier you control. Prevent all damage that would be dealt to other attacking Soldiers you control. | Jesper Ejsing

Geology Enthusiast | Creature | Human Artificer | At the beginning of your end step, create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.") {6}: Draw a card and put a +1/+1 counter on Geology Enthusiast. | Fajareka Setiawan

Gix's Command | Sorcery | | Choose two — • Put two +1/+1 counter on up to one creature. It gains lifelink until end of turn. • Destroy each creature with power 2 or less. • Return up to two creature cards from your graveyard to your hand. • Each opponent sacrifices a creature with the highest power among creatures they control. | Dominik Mayer

Painful Quandary | Enchantment | | Whenever an opponent casts a spell, that player loses 5 life unless they discard a card. | David Palumbo

Tawnos, the Toymaker | Legendary Creature | Human Artificer | Whenever you cast a Beast or Bird creature spell, you may copy it, except the copy is an artifact in addition to its other types. (The copy becomes a token.) | Livia Prima

Mishra, Tamer of Mak Fawa | Legendary Creature | Human Artificer | Permanents you control have "Ward—Sacrifice a permanent." Each artifact card in your graveyard has unearth {1}{B}{R}. ({1}{B}{R}: Return the 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.) | Darren Tan

Deathbloom Ritualist | Creature | Elf Warlock | {T}: Add X mana of any one color, where X is the number of creature cards in your graveyard. | Taras Susak

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

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

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