Mirran Mettle

Target creature gets +2/+2 until end of turn.
Metalcraft — That creature gets +4/+4 until end of turn instead if you control three or more artifacts.

Distant Memories

Search your library for a card, exile it, then shuffle. Any opponent may have you put that card into your hand. If no player does, you draw three cards.

Deathbringer Thoctar

Whenever another creature dies, you may put a +1/+1 counter on Deathbringer Thoctar.
Remove a +1/+1 counter from Deathbringer Thoctar: It deals 1 damage to any target.

Malfegor

Flying
When Malfegor enters, discard your hand. Each opponent sacrifices a creature of their choice for each card discarded this way.

Nim Deathmantle

Equipped creature gets +2/+2, has intimidate, and is a black Zombie. (A creature with intimidate can’t be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a nontoken creature is put into your graveyard from the battlefield, you may pay . If you do, return that card to the battlefield and attach Nim Deathmantle to it.
Equip

Vedalken Certarch

Metalcraft — : Tap target artifact, creature, or land. Activate only if you control three or more artifacts.

Ezuri, Renegade Leader

: Regenerate another target Elf.
: Elf creatures you control get +3/+3 and gain trample until end of turn.

Kor Aeronaut

Kicker (You may pay an additional as you cast this spell.)
Flying
When Kor Aeronaut enters, if it was kicked, target creature gains flying until end of turn.

Aether Vial

At the beginning of your upkeep, you may put a charge counter on Aether Vial.
: You may put a creature card with mana value equal to the number of charge counters on Aether Vial from your hand onto the battlefield.

Acidic Slime

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When Acidic Slime enters, destroy target artifact, enchantment, or land.

Elvish Archdruid

Other Elf creatures you control get +1/+1.
: Add for each Elf you control.

Stormtide Leviathan

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
All lands are Islands in addition to their other types.
Creatures without flying or islandwalk can’t attack.

Infest

All creatures get -2/-2 until end of turn.

Curse of Wizardry

As Curse of Wizardry enters, choose a color.
Whenever a player casts a spell of the chosen color, that player loses 1 life.

Magmaw

, Sacrifice a nonland permanent: Magmaw deals 1 damage to any target.

Guard Duty

Enchant creature
Enchanted creature has defender.