Chitterspitter

At the beginning of your upkeep, you may sacrifice a token. If you do, put an acorn counter on Chitterspitter.
Squirrels you control get +1/+1 for each acorn counter on Chitterspitter.
{G}, {T}: Create a 1/1 green Squirrel creature token.

Livio, Oathsworn Sentinel

{1}{W}: Choose another target creature. Its controller may exile it with an aegis counter on it.
{2}{W}, {T}: Return all exiled cards with aegis counters on them to the battlefield under their owners' control.
Partner (You can have two commanders if both have partner.)

Liege of the Tangle

Trample
Whenever Liege of the Tangle deals combat damage to a player, you may choose any number of target lands you control and put an awakening counter on each of them. Each of those lands is an 8/8 green Elemental creature for as long as it has an awakening counter on it. They're still lands.

Atraxa, Praetors' Voice

Flying, vigilance, deathtouch, lifelink
At the beginning of your end step, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Rottenmouth Viper

As an additional cost to cast this spell, you may sacrifice any number of nonland permanents. This spell costs {1} less to cast for each permanent sacrificed this way.
Whenever Rottenmouth Viper enters or attacks, put a blight counter on it. Then for each blight counter on it, each opponent loses 4 life unless that player sacrifices a nonland permanent of their choice or discards a card.

Contagion

You may pay 1 life and exile a black card from your hand rather than pay this spell's mana cost.
Distribute two -2/-1 counters among one or two target creatures.

Fungus Elemental

{G}, Sacrifice a Forest: Put a +2/+2 counter on Fungus Elemental. Activate only if Fungus Elemental entered this turn.

Shield Sphere

Defender
Whenever Shield Sphere blocks, put a -0/-1 counter on it.

Clockwork Steed

Clockwork Steed enters with four +1/+0 counters on it.
Clockwork Steed can't be blocked by artifact creatures.
At end of combat, if Clockwork Steed attacked or blocked this combat, remove a +1/+0 counter from it.
{X}, {T}: Put up to X +1/+0 counters on Clockwork Steed. This ability can't cause the total number of +1/+0 counters on Clockwork Steed to be greater than four. Activate only during your upkeep.

Gwafa Hazid, Profiteer

{W}{U}, {T}: Put a bribery counter on target creature you don't control. Its controller draws a card.
Creatures with bribery counters on them can't attack or block.

Clockwork Swarm

Clockwork Swarm enters with four +1/+0 counters on it.
Clockwork Swarm can't be blocked by Walls.
At end of combat, if Clockwork Swarm attacked or blocked this combat, remove a +1/+0 counter from it.
{X}, {T}: Put up to X +1/+0 counters on Clockwork Swarm. This ability can't cause the total number of +1/+0 counters on Clockwork Swarm to be greater than four. Activate only during your upkeep.

Sunset Pyramid

Sunset Pyramid enters with three brick counters on it.
{2}, {T}, Remove a brick counter from Sunset Pyramid: Draw a card.
{2}, {T}: Scry 1.

Edgar Markov's Coffin

At the beginning of your upkeep, create a 1/1 white and black Vampire creature token with lifelink and put a bloodline counter on Edgar Markov's Coffin. Then if there are three or more bloodline counters on it, remove those counters and transform it.

Edgar, Charmed Groom

Other Vampires you control get +1/+1.
When Edgar, Charmed Groom dies, return it to the battlefield transformed under its owner's control.

Edgar, Charmed Groom // Edgar Markov's Coffin

Fishing Pole

Equipped creature has "{1}, {T}, Tap Fishing Pole: Put a bait counter on Fishing Pole."
Whenever equipped creature becomes untapped, remove a bait counter from this Equipment. If you do, create a 1/1 blue Fish creature token.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Rayami, First of the Fallen

If a nontoken creature would die, exile that card with a blood counter on it instead.
As long as an exiled creature card with a blood counter on it has flying, Rayami, First of the Fallen has flying. The same is true for first strike, double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, protection, reach, trample, and vigilance.

Spell Satchel

Magecraft — Whenever you cast or copy an instant or sorcery spell, put a book counter on Spell Satchel.
{T}, Remove a book counter from Spell Satchel: Add {C}.
{3}, {T}, Remove three book counters from Spell Satchel: Draw a card.

Rex, Cyber-Hound

Whenever Rex, Cyber-Hound deals combat damage to a player, they mill two cards and you get {E}{E} (two energy counters).
Pay {E}{E}: Choose target creature card in a graveyard. Exile it with a brain counter on it. Activate only as a sorcery.
Rex has all activated abilities of all cards in exile with brain counters on them.

Blood Spatter Analysis

When Blood Spatter Analysis enters, it deals 3 damage to target creature an opponent controls.
Whenever one or more creatures die, mill a card and put a bloodstain counter on Blood Spatter Analysis. Then sacrifice it if it has five or more bloodstain counters on it. When you do, return target creature card from your graveyard to your hand.

Frankenstein's Monster

As Frankenstein's Monster enters, exile X creature cards from your graveyard. If you can't, put Frankenstein's Monster into its owner's graveyard instead of onto the battlefield. For each creature card exiled this way, Frankenstein's Monster enters with a +2/+0, +1/+1, or +0/+2 counter on it.

Ebon Praetor

First strike, trample
At the beginning of your upkeep, put a -2/-2 counter on Ebon Praetor.
Sacrifice a creature: Remove a -2/-2 counter from Ebon Praetor. If the sacrificed creature was a Thrull, put a +1/+0 counter on Ebon Praetor. Activate only during your upkeep and only once each turn.

Hankyu

Equipped creature has "{T}: Put an aim counter on Hankyu" and "{T}, Remove all aim counters from Hankyu: This creature deals damage to any target equal to the number of aim counters removed this way."
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

Archery Training

Enchant creature
At the beginning of your upkeep, you may put an arrow counter on Archery Training.
Enchanted creature has "{T}: This creature deals X damage to target attacking or blocking creature, where X is the number of arrow counters on Archery Training."

Chevill, Bane of Monsters

Deathtouch
At the beginning of your upkeep, if your opponents control no permanents with bounty counters on them, put a bounty counter on target creature or planeswalker an opponent controls.
Whenever a permanent an opponent controls with a bounty counter on it dies, you gain 3 life and draw a card.

Coral Reef

Coral Reef enters with four polyp counters on it.
Sacrifice an Island: Put two polyp counters on Coral Reef.
{U}, Tap an untapped blue creature you control, Remove a polyp counter from Coral Reef: Put a +0/+1 counter on target creature.

The One Ring

Indestructible
When The One Ring enters, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Boon of the Spirit Realm

Constellation — Whenever Boon of the Spirit Realm or another enchantment you control enters, put a blessing counter on Boon of the Spirit Realm.
Creatures you control get +1/+1 for each blessing counter on Boon of the Spirit Realm.

Essence Flare

Enchant creature
Enchanted creature gets +2/+0.
At the beginning of the upkeep of enchanted creature's controller, put a -0/-1 counter on that creature.

Armor Thrull

{T}, Sacrifice Armor Thrull: Put a +1/+2 counter on target creature.

Obsidian Fireheart

{1}{R}{R}: Put a blaze counter on target land without a blaze counter on it. For as long as that land has a blaze counter on it, it has "At the beginning of your upkeep, this land deals 1 damage to you." (The land continues to burn after Obsidian Fireheart has left the battlefield.)

Spirit Shackle

Enchant creature
Whenever enchanted creature becomes tapped, put a -0/-2 counter on it.

Jabari's Influence

Cast this spell only after combat.
Gain control of target nonartifact, nonblack creature that attacked you this turn and put a -1/-0 counter on it.

Malignant Growth

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
At the beginning of your upkeep, put a growth counter on Malignant Growth.
At the beginning of each opponent's draw step, that player draws an additional card for each growth counter on Malignant Growth, then Malignant Growth deals damage to the player equal to the number of cards they drew this way.

Wall of Resistance

Defender (This creature can't attack.)
Flying
At the beginning of each end step, if Wall of Resistance was dealt damage this turn, put a +0/+1 counter on it.

Serrated Arrows

Serrated Arrows enters with three arrowhead counters on it.
At the beginning of your upkeep, if there are no arrowhead counters on Serrated Arrows, sacrifice it.
{T}, Remove an arrowhead counter from Serrated Arrows: Put a -1/-1 counter on target creature.