Razzle-Dazzler

Whenever you cast your second spell each turn, put a +1/+1 counter on this creature. It can't be blocked this turn.

Farmstead Gleaner

This creature doesn't untap during your untap step.
{2}, {Q}: Put a +1/+1 counter on this creature. ({Q} is the untap symbol.)

Cloudfin Raptor

Flying
Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Erudite Wizard

Whenever you draw your second card each turn, put a +1/+1 counter on this creature.

Nadir Kraken

Whenever you draw a card, you may pay {1}. If you do, put a +1/+1 counter on this creature and create a 1/1 blue Tentacle creature token.

Piper Wright, Publick Reporter

Whenever Piper Wright deals combat damage to a player, investigate that many times. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Whenever you sacrifice a Clue, put a +1/+1 counter on target creature you control.

Faerie Vandal

Flash (You may cast this spell any time you could cast an instant.)
Flying
Whenever you draw your second card each turn, put a +1/+1 counter on this creature.

Chrome Host Seedshark

Flying
Whenever you cast a noncreature spell, incubate X, where X is that spell's mana value. (Create an Incubator token with X +1/+1 counters on it and "{2}: Transform this token." It transforms into a 0/0 Phyrexian artifact creature.)

Rug of Smothering

Flying
Whenever a player casts a spell, they lose 1 life for each spell they've cast this turn.

Thopter Mechanic

Whenever you draw your second card each turn, put a +1/+1 counter on this creature.
When this creature dies, create a 1/1 colorless Thopter artifact creature token with flying.

Iymrith, Desert Doom

Flying
Iymrith has ward {4} as long as it's untapped.
Whenever Iymrith deals combat damage to a player, draw a card. Then if you have fewer than three cards in hand, draw cards equal to the difference.

Malcolm, Keen-Eyed Navigator

Flying
Whenever one or more Pirates you control deal damage to your opponents, you create a Treasure token for each opponent dealt damage. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
Partner (You can have two commanders if both have partner.)

Ledger Shredder

Flying
Whenever a player casts their second spell each turn, this creature connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)

Liberator, Urza's Battlethopter

Flash
Flying
You may cast colorless spells and artifact spells as though they had flash.
Whenever you cast a spell, if the amount of mana spent to cast that spell is greater than Liberator's power, put a +1/+1 counter on Liberator.

Brineborn Cutthroat

Flash (You may cast this spell any time you could cast an instant.)
Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on this creature.

Storm Fleet Negotiator

Flying
Parley — Whenever this creature attacks, each player reveals the top card of their library. For each nonland card revealed this way, you create a Map token. Then each player draws a card. (A Map token is an artifact with "{1}, {T}, Sacrifice this token: Target creature you control explores. Activate only as a sorcery.")

Spectral Adversary

Flash
Flying
When this creature enters, you may pay {1}{U} any number of times. When you pay this cost one or more times, put that many +1/+1 counters on this creature, then up to that many other target artifacts, creatures, and/or enchantments phase out.

Stratus Dancer

Flying
Megamorph {1}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When this creature is turned face up, counter target instant or sorcery spell.

Patchwork Crawler

{2}{U}: Exile target creature card from your graveyard and put a +1/+1 counter on this creature.
This creature has all activated abilities of all creature cards exiled with it.

Diamond Knight

Vigilance (Attacking doesn't cause this creature to tap.)
As this creature enters, choose a color.
Whenever you cast a spell of the chosen color, put a +1/+1 counter on this creature.

Geralf, the Fleshwright

Whenever you cast a spell during your turn other than your first spell that turn, create a 2/2 blue and black Zombie Rogue creature token.
Whenever a Zombie you control enters, put a +1/+1 counter on it for each other Zombie that entered the battlefield under your control this turn.

Trawler Drake

Flying
This creature enters with an oil counter on it.
This creature gets +1/+1 for each oil counter on it.
Whenever you cast a noncreature spell, put an oil counter on this creature.

Ascendant Spirit

{S}{S}: This creature becomes a Spirit Warrior with base power and toughness 2/3.
{S}{S}{S}: If this creature is a Warrior, put a flying counter on it and it becomes a Spirit Warrior Angel with base power and toughness 4/4.
{S}{S}{S}{S}: If this creature is an Angel, put two +1/+1 counters on it and it gains "Whenever this creature deals combat damage to a player, draw a card."

Epochrasite

This creature enters with three +1/+1 counters on it if you didn't cast it from your hand.
When this creature dies, exile it with three time counters on it and it gains suspend. (At the beginning of its owner's upkeep, they remove a time counter. When the last is removed, they may cast this card without paying its mana cost. It has haste.)

The Omenkeel

Whenever a Vehicle you control deals combat damage to a player, that player exiles that many cards from the top of their library. You may play lands from among those cards for as long as they remain exiled.
Crew 1

Cosima, God of the Voyage

At the beginning of your upkeep, you may exile Cosima. If you do, it gains "Whenever a land you control enters, if Cosima is exiled, you may put a voyage counter on it. If you don't, return Cosima to the battlefield with X +1/+1 counters on it and draw X cards, where X is the number of voyage counters on it."

Cosima, God of the Voyage // The Omenkeel

Benthic Biomancer

{1}{U}: Adapt 1. (If this creature has no +1/+1 counters on it, put a +1/+1 counter on it.)
Whenever one or more +1/+1 counters are put on this creature, draw a card, then discard a card.

Talion's Messenger

Flying
Whenever you attack with one or more Faeries, draw a card, then discard a card. When you discard a card this way, put a +1/+1 counter on target Faerie you control.

Bloodline Pretender

Changeling (This card is every creature type.)
As this creature enters, choose a creature type.
Whenever another creature you control of the chosen type enters, put a +1/+1 counter on this creature.

Aven Eternal

Flying
When this creature enters, amass Zombies 1. (Put a +1/+1 counter on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)

Tempest Djinn

Flying
This creature gets +1/+0 for each basic Island you control.

Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on this creature.
When this creature dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on this creature. (They can't be blocked as long as defending player controls an Island.)

Silent Hallcreeper

This creature can't be blocked.
Whenever this creature deals combat damage to a player, choose one that hasn't been chosen —
• Put two +1/+1 counters on this creature.
• Draw a card.
• This creature becomes a copy of another target creature you control.

Arcbound Slith

Whenever this creature deals combat damage to a player, put a +1/+1 counter on it.
Modular 1 (This creature enters with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)