Aethershield Artificer

At the beginning of combat on your turn, target artifact creature you control gets +2/+2 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Torbran, Thane of Red Fell

If a red source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.

Audacious Infiltrator

Audacious Infiltrator can't be blocked by artifact creatures.

Depala, Pilot Exemplar

Other Dwarves you control get +1/+1.
Each Vehicle you control gets +1/+1 as long as it's a creature.
Whenever Depala, Pilot Exemplar becomes tapped, you may pay {X}. If you do, reveal the top X cards of your library, put all Dwarf and Vehicle cards from among them into your hand, then put the rest on the bottom of your library in a random order.

Aerial Responder

Axgard Braggart

Boast — {1}{W}: Untap Axgard Braggart. Put a +1/+1 counter on it. (Activate only if this creature attacked this turn and only once each turn.)

Dwarven Armorer

{R}, {T}, Discard a card: Put a +0/+1 counter or a +1/+0 counter on target creature.

Airdrop Aeronauts

Flying
Revolt — When Airdrop Aeronauts enters, if a permanent you controlled left the battlefield this turn, you gain 5 life.

Bomb Squad

{T}: Put a fuse counter on target creature.
At the beginning of your upkeep, put a fuse counter on each creature with a fuse counter on it.
Whenever a creature has four or more fuse counters on it, remove all fuse counters from it and destroy it. That creature deals 4 damage to its controller.