War of the Spark

Challenger Troll | Creature | Troll | Each creature you control with power 4 or greater can't be blocked by more than one creature. | Svetlin Velinov

Evolution Sage | Creature | Elf Druid | Landfall — Whenever a land enters the battlefield under your control, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.) | Simon Dominic

Mowu, Loyal Companion | Legendary Creature | Dog | Vigilance, trample If one or more +1/+1 counters would be put on Mowu, Loyal Companion, that many plus one +1/+1 counters are put on it instead. | Kimonas Theodossiou

Paradise Druid | Creature | Elf Druid | Paradise Druid has hexproof as long as it's untapped. (It can't be the target of spells or abilities your opponents control.) {T}: Add one mana of any color. | Nils Hamm

Huatli's Raptor | Creature | Dinosaur | Vigilance When Huatli's Raptor enters the battlefield, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.) | Randy Vargas

Merfolk Skydiver | Creature | Merfolk Mutant | Flying When Merfolk Skydiver enters the battlefield, put a +1/+1 counter on target creature you control. {3}{G}{U}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.) | Sara Winters

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