War of the Spark

Feather, the Redeemed | Legendary Creature | Angel | Flying Whenever you cast an instant or sorcery spell that targets a creature you control, exile that card instead of putting it into your graveyard as it resolves. If you do, return it to your hand at the beginning of the next end step. | Wayne Reynolds

Tenth District Legionnaire | Creature | Human Soldier | Haste Whenever you cast a spell that targets Tenth District Legionnaire, put a +1/+1 counter on Tenth District Legionnaire, then scry 1. | Victor Adame Minguez

Dreadhorde Butcher | Creature | Zombie Warrior | Haste Whenever Dreadhorde Butcher deals combat damage to a player or planeswalker, put a +1/+1 counter on Dreadhorde Butcher. When Dreadhorde Butcher dies, it deals damage equal to its power to any target. | Piotr Dura

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

Living Twister | Creature | Elemental | {1}{R}, Discard a land card: Living Twister deals 2 damage to any target. {G}: Return a tapped land you control to its owner's hand. | James Paick

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

Niv-Mizzet Reborn | Legendary Creature | Dragon Avatar | Flying When Niv-Mizzet Reborn enters the battlefield, reveal the top ten cards of your library. For each color pair, choose a card that's exactly those colors from among them. Put the chosen cards into your hand and the rest on the bottom of your library in a random order. | Raymond Swanland