The Brothers' War

Argothian Opportunist | Creature | Human Scout | When Argothian Opportunist enters the battlefield, create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.") | Ina Wong

Burrowing Razormaw | Creature | Beast | When Burrowing Razormaw dies, mill four cards. (Put the top four cards of your library into your graveyard.) | Uriah Voth

Gwenna, Eyes of Gaea | Legendary Creature | Elf Druid Scout | {T}: Add two mana in any combination of colors. Spend this mana only to cast creature spells or activate abilities of a creature or creature card. Whenever you cast a creature spell with power 5 or greater, put a +1/+1 counter on Gwenna, Eyes of Gaea and untap it. | Steve Prescott

Perimeter Patrol | Creature | Human Soldier | Whenever an artifact enters the battlefield under your control, Perimeter Patrol gets +1/+0 until end of turn. | Edgar Sánchez Hidalgo

Titania, Voice of Gaea | Legendary Creature | Elemental | Reach Whenever one or more land cards are put into your graveyard from anywhere, you gain 2 life. At the beginning of your upkeep, if there are four or more land cards in your graveyard and you both own and control Titania, Voice of Gaea and a land named Argoth, Sanctum of Nature, exile them, then meld them into Titania, Gaea Incarnate. | Cristi Balanescu

Arbalest Engineers | Creature | Human Artificer | When Arbalest Engineers enters the battlefield, choose one — • Arbalest Engineers deals 1 damage to any target. • Put a +1/+1 counter on target creature. It gains trample and haste until end of turn. • Create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.") | Marta Nael

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