Oath of Teferi Oath of Teferi is the most obvious choice from past cards, and rather than going in chronological order I'm starting with this five-mana enchantment because of what we already know about WAR: that there's going to be one planeswalker in every pack
When this Aura enters, exile up to one target creature other than enchanted creature until this Aura leaves the battlefield
Technically, there are also tons of other combos

A Real Handful Abomination of Llanowar Abomination, World Ravager Absolving Lammasu Achilles Davenport Agent Venom Agents of HYDRA Aggressive Symbiosis Agrus Kos, Spirit of Justice Akroma, Vision of Ixidor Alien Symbiosis Alley Strangler Alpha Deathclaw Altar of Bhaal Altar of Bhaal Amzu, Swarm's Hunger Angrath, Captain of Chaos Anikthea, Hand of Erebos Animus of Night's Reach Animus of Predation Aradara Express Arcbound Tracker Ardbert, Warrior of Darkness Ardyn, the Usurper Arm-Mounted Anchor Armed Assailant Armory Veteran Arnim Zola, Bio-Fanatic Aron, Benalia's Ruin Artillery Enthusiast Ashen Reaper Aspiring Champion Assault Intercessor Atarka Pummeler Atris, Oracle of Half-Truths Avalanche of Sector 7 Avengers: Under Siege Aya of Alexandria Ayara's Oathsworn Azula, Ruthless Firebender Balduvian Atrocity Baleful Beholder Baral and Kari Zev Barbarian Class Barbed Servitor Battlesong Berserker Beamtown Beatstick Bebop, Warthog Warrior Bedhead Beastie Belle of the Brawl Belligerent Sliver Belligerent of the Ball Bismuth Mindrender Biting-Palm Ninja Black Widow, Agile Avenger Black Widow, Daring Operative Black Widow, Double Agent Black Widow, Super Spy Blackbloom Rogue Blade of the Oni Bladegraft Aspirant Bladewing, Deathless Tyrant Bleeding Effect Blight Mound Blood Curdle Blood Researcher Blood-Chin Rager Bloodcrazed Socialite Bloodsky Berserker Bloodstone Goblin Body Dropper Bog Badger

*Printings of cards may vary depending on availability
X: Huatli deals X damage divided as you choose among any number of target creatures