Cazur, Ruthless Stalker

Partner with Ukkima, Stalking Shadow (When this creature enters, target player may put Ukkima into their hand from their library, then shuffle.)
Whenever a creature you control deals combat damage to a player, put a +1/+1 counter on that creature.

Acidic Slime

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

Citanul Stalwart

{T}, Tap an untapped artifact or creature you control: Add one mana of any color.

Alpine Grizzly

Spider Umbra

Enchant creature
Enchanted creature gets +1/+1 and has reach. (It can block creatures with flying.)
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Aerial Predation

Destroy target creature with flying. You gain 2 life.

Aloe Alchemist

Trample
When this card becomes plotted, target creature gets +3/+2 and gains trample until end of turn.
Plot {1}{G} (You may pay {1}{G} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Berserk Murlodont

Whenever a Beast becomes blocked, it gets +1/+1 until end of turn for each creature blocking it.

Preposterous Proportions

Creatures you control get +10/+10 and gain vigilance until end of turn.

Accomplished Alchemist

{T}: Add one mana of any color.
{T}: Add X mana of any one color, where X is the amount of life you gained this turn.

Aim High

Untap target creature. It gets +2/+2 and gains reach until end of turn.

Elvish Herder

{G}: Target creature gains trample until end of turn.

Ankle Biter

Awaken the Bear

Target creature gets +3/+3 and gains trample until end of turn.

Bestow Greatness

Target creature gets +4/+4 and gains trample until end of turn.

Blanchwood Armor

Enchant creature
Enchanted creature gets +1/+1 for each Forest you control.

Curse of Predation

Enchant player
Whenever a creature attacks enchanted player, put a +1/+1 counter on it.

Adaptive Shimmerer

Flash
This creature enters with three +1/+1 counters on it.

Abundant Growth

Enchant land
When this Aura enters, draw a card.
Enchanted land has "{T}: Add one mana of any color."

Accelerated Mutation

Target creature gets +X/+X until end of turn, where X is the greatest mana value among permanents you control.

Defiant Elf

Knickknack Ouphe

This creature enters with X +1/+1 counters on it.
When this creature enters, reveal the top X cards of your library. You may put any number of Aura cards with mana value X or less from among them onto the battlefield. Then put all cards revealed this way that weren't put onto the battlefield on the bottom of your library in a random order.

Arbor Armament

Put a +1/+1 counter on target creature. That creature gains reach until end of turn. (It can block creatures with flying.)

Arbor Adherent

{T}: Add one mana of any color.
{T}: Add X mana of any one color, where X is the greatest toughness among other creatures you control.

Crystal Carapace

Enchant creature
Enchanted creature gets +3/+3 and has ward {2}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Cryptid Inspector

Vigilance
Whenever a face-down permanent you control enters and whenever this creature or another permanent you control is turned face up, put a +1/+1 counter on this creature.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Anara, Wolvid Familiar

During your turn, commanders you control have indestructible. (Effects that say "destroy" don't destroy them. A creature with indestructible can't be destroyed by damage.)
Partner (You can have two commanders if both have partner.)

Bottle Gnomes

Sacrifice this creature: You gain 3 life.

Birds of Paradise

Canopy Tactician

Other Elves you control get +1/+1.
{T}: Add {G}{G}{G}.

Ambassador Oak

When this creature enters, create a 1/1 green Elf Warrior creature token.

Agatha's Champion

Bargain (You may sacrifice an artifact, enchantment, or token as you cast this spell.)
Trample
When this creature enters, if it was bargained, it fights up to one target creature you don't control. (Each deals damage equal to its power to the other.)

Epic Proportions

Flash
Enchant creature
Enchanted creature gets +5/+5 and has trample.

Forest

Eldrazi Conscription

Enchant creature
Enchanted creature gets +10/+10 and has trample and annihilator 2. (Whenever it attacks, defending player sacrifices two permanents of their choice.)

Arachnoform

Enchant creature
Enchanted creature gets +2/+2, has reach, and is every creature type.

Kamahl, Heart of Krosa

At the beginning of combat on your turn, creatures you control get +3/+3 and gain trample until end of turn.
{1}{G}: Until end of turn, target land you control becomes a 1/1 Elemental creature with vigilance, indestructible, and haste. It's still a land.
Partner (You can have two commanders if both have partner.)

Ajani's Comrade

Trample
At the beginning of combat on your turn, if you control an Ajani planeswalker, put a +1/+1 counter on this creature.

Ainok Guide

When this creature enters, choose one —
• Put a +1/+1 counter on this creature.
• Search your library for a basic land card, reveal it, then shuffle and put that card on top.

Ageless Entity

Whenever you gain life, put that many +1/+1 counters on this creature.

Dwynen, Gilt-Leaf Daen

Reach (This creature can block creatures with flying.)
Other Elf creatures you control get +1/+1.
Whenever Dwynen attacks, you gain 1 life for each attacking Elf you control.

Birthing Hulk

Devoid (This card has no color.)
When this creature enters, create two 1/1 colorless Eldrazi Scion creature tokens. They have "Sacrifice this token: Add {C}." ({C} represents colorless mana.)
{1}{C}: Regenerate this creature.

Bassara Tower Archer

Elvish Aberration

{T}: Add {G}{G}{G}.
Forestcycling {2} ({2}, Discard this card: Search your library for a Forest card, reveal it, put it into your hand, then shuffle.)

Sol Ring

Burlfist Oak

Whenever you draw a card, this creature gets +2/+2 until end of turn.

Arachnoid Adaptation

Target creature gets +2/+2 and gains reach until end of turn. Untap it.

Decorated Champion

Whenever another Warrior your team controls enters, put a +1/+1 counter on this creature.

Druid of the Cowl

Curse of Clinging Webs

Enchant player
Whenever a nontoken creature enchanted player controls dies, exile it and you create a 1/2 green Spider creature token with reach.

Ambush Viper

Lion Umbra

Enchant modified creature (Equipment, Auras its controller controls, and counters are modifications.)
Enchanted creature gets +3/+3 and has vigilance and reach.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Deathbloom Gardener

Deathtouch
{T}: Add one mana of any color.

Ashaya, Soul of the Wild

Ashaya's power and toughness are each equal to the number of lands you control.
Nontoken creatures you control are Forest lands in addition to their other types. (They're still affected by summoning sickness.)

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Celeborn the Wise

Whenever you attack with one or more Elves, scry 1.
Whenever you scry, Celeborn gets +1/+1 until end of turn for each card looked at while scrying this way.

Arbor Elf

Kurbis, Harvest Celebrant

Kurbis enters with a number of +1/+1 counters on it equal to the amount of mana spent to cast it.
Remove a +1/+1 counter from Kurbis: Prevent all damage that would be dealt this turn to another target creature with a +1/+1 counter on it.