War of the Spark

Dovin, Hand of Control | Legendary Planeswalker | Dovin | Artifact, instant, and sorcery spells your opponents cast cost {1} more to cast. −1: Until your next turn, prevent all damage that would be dealt to and dealt by target permanent an opponent controls. | Kieran Yanner

Pledge of Unity | Instant | | Put a +1/+1 counter on each creature you control. You gain 1 life for each creature you control. | Chris Rallis

Huatli, the Sun's Heart | Legendary Planeswalker | Huatli | Each creature you control assigns combat damage equal to its toughness rather than its power. −3: You gain life equal to the greatest toughness among creatures you control. | Lius Lasahido

Gleaming Overseer | Creature | Zombie Wizard | When Gleaming Overseer enters the battlefield, amass 1. (Put a +1/+1 counter on an Army you control. If you don't control one, create a 0/0 black Zombie Army creature token first.) Zombie tokens you control have hexproof and menace. | Volkan Baǵa

Ashiok, Dream Render | Legendary Planeswalker | Ashiok | Spells and abilities your opponents control can't cause their controller to search their library. −1: Target player mills four cards. Then exile each opponent's graveyard. | Cynthia Sheppard

Invade the City | Sorcery | | Amass X, where X is the number of instant and sorcery cards in your graveyard. (Put X +1/+1 counters on an Army you control. If you don't control one, create a 0/0 black Zombie Army creature token first.) | Sung Choi

Saheeli, Sublime Artificer | Legendary Planeswalker | Saheeli | Whenever you cast a noncreature spell, create a 1/1 colorless Servo artifact creature token. −2: Target artifact you control becomes a copy of another target artifact or creature you control until end of turn, except it's an artifact in addition to its other types. | Wesley Burt

Kiora, Behemoth Beckoner | Legendary Planeswalker | Kiora | Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card. −1: Untap target permanent. | Jaime Jones

Mayhem Devil | Creature | Devil | Whenever a player sacrifices a permanent, Mayhem Devil deals 1 damage to any target. | Dmitry Burmak

Leyline Prowler | Creature | Nightmare Beast | Deathtouch, lifelink {T}: Add one mana of any color. | YW Tang

Rubblebelt Rioters | Creature | Human Berserker | Haste Whenever Rubblebelt Rioters attacks, it gets +X/+0 until end of turn, where X is the greatest power among creatures you control. | Tomasz Jedruszek