Have

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

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.)

Essence Capture

Counter target creature spell. Put a +1/+1 counter on up to one target creature you control.

Ashnod's Transmogrant

{T}, Sacrifice this artifact: Put a +1/+1 counter on target nonartifact creature. That creature becomes an artifact in addition to its other types.

Wrong Turn

Target opponent gains control of target creature. (If an attacking or blocking creature changes controllers, it's removed from combat.)

Aether Tradewinds

Return target permanent you control and target permanent you don't control to their owners' hands.

Blustersquall

Tap target creature you don't control.
Overload {3}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Dreamtide Whale

Vanishing 2 (This creature enters with two time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Whenever a player casts their second spell each turn, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Emrakul's Messenger

Devoid (This card has no color.)
Flying
Whenever you draw your second card each turn, create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this token: Add {C}."

Nardole, Resourceful Cyborg

{T}: Add {U} for each counter on Nardole. Spend this mana only to cast noncreature spells.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)
Doctor's companion (You can have two commanders if the other is the Doctor.)

Goldberry, River-Daughter

{T}: Move a counter of each kind not on Goldberry from another target permanent you control onto Goldberry.
{U}, {T}: Move one or more counters from Goldberry onto another target permanent you control. If you do, draw a card.

Flow of Knowledge

Draw a card for each Island you control, then discard two cards.

Sparring Construct

When this creature dies, put a +1/+1 counter on target creature you control.

Jace's Projection

Whenever you draw a card, put a +1/+1 counter on this creature.
{3}{U}: Put a loyalty counter on target Jace planeswalker.

Mindless Automaton

This creature enters with two +1/+1 counters on it.
{1}, Discard a card: Put a +1/+1 counter on this creature.
Remove two +1/+1 counters from this creature: Draw a card.

Shifting Wall

Defender (This creature can't attack.)
This creature enters with X +1/+1 counters on it.

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.

Knights of Dol Amroth

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

Duelist of the Mind

Flying, vigilance
Duelist of the Mind's power is equal to the number of cards you've drawn this turn.
Whenever you commit a crime, you may draw a card. If you do, discard a card. This ability triggers only once each turn.

Arcbound Worker

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.)

Flux Channeler

Whenever you cast a noncreature spell, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Temporal Fissure

Return target permanent to its owner's hand.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Mind Games

Buyback {2}{U} (You may pay an additional {2}{U} as you cast this spell. If you do, put this card into your hand as it resolves.)
Tap target artifact, creature, or land.

Erudite Wizard

Sky Diamond

This artifact enters tapped.
{T}: Add {U}.

Pyramid of the Pantheon

{2}, {T}: Add one mana of any color. Put a brick counter on this artifact.
{T}: Add three mana of any one color. Activate only if there are three or more brick counters on this artifact.

Danny Pink

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Creatures you control have "Whenever one or more counters are put on this creature for the first time each turn, draw a card."

Contempt

Enchant creature
When enchanted creature attacks, return it and this Aura to their owners' hands at end of combat.

Reality Ripple

Target artifact, creature, or land phases out. (While it's phased out, it's treated as though it doesn't exist. It phases in before its controller untaps during their next untap step.)

Energy Tap

Tap target untapped creature you control. If you do, add an amount of {C} equal to that creature's mana value.

Fact or Fiction

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

This Town Ain't Big Enough

This spell costs {3} less to cast if it targets a permanent you control.
Return up to two target nonland permanents to their owners' hands.

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.

Ensnare

You may return two Islands you control to their owner's hand rather than pay this spell's mana cost.
Tap all creatures.

Clockwork Beetle

This creature enters with two +1/+1 counters on it.
Whenever this creature attacks or blocks, remove a +1/+1 counter from it at end of combat.

Island

Thrummingbird

Flying
Whenever this creature deals combat damage to a player, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Aether Spellbomb

{U}, Sacrifice this artifact: Return target creature to its owner's hand.
{1}, Sacrifice this artifact: Draw a card.

Hangarback Walker

This creature enters with X +1/+1 counters on it.
When this creature dies, create a 1/1 colorless Thopter artifact creature token with flying for each +1/+1 counter on this creature.
{1}, {T}: Put a +1/+1 counter on this creature.

Sleep

Tap all creatures target player controls. Those creatures don't untap during that player's next untap step.

Myr Scrapling

Sacrifice this creature: Put a +1/+1 counter on target creature.

Thwart

You may return three Islands you control to their owner's hand rather than pay this spell's mana cost.
Counter target spell.

Coretapper

{T}: Put a charge counter on target artifact.
Sacrifice this creature: Put two charge counters on target artifact.

Oneirophage

Flying
Whenever you draw a card, put a +1/+1 counter on this creature.

Iron Apprentice

This creature enters with a +1/+1 counter on it.
When this creature dies, if it had counters on it, put those counters on target creature you control.

Zephyr Singer

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Flying, vigilance
When this creature enters, put a flying counter on each creature that convoked it.

Thopter Squadron

Flying
This creature enters with three +1/+1 counters on it.
{1}, Remove a +1/+1 counter from this creature: Create a 1/1 colorless Thopter artifact creature token with flying. Activate only as a sorcery.
{1}, Sacrifice another Thopter: Put a +1/+1 counter on this creature. Activate only as a sorcery.

Boomerang

Return target permanent to its owner's hand.

Alexi's Cloak

Flash
Enchant creature
Enchanted creature has shroud. (It can't be the target of spells or abilities.)

Intervene

Counter target spell that targets a creature.

Spellbook

Mana Leak

Counter target spell unless its controller pays {3}.

Unsummon

Return target creature to its owner's hand.

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.

Deepglow Skate

When this creature enters, double the number of each kind of counter on any number of target permanents.

Leap

Target creature gains flying until end of turn.
Draw a card.

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.

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Curfew

Each player returns a creature they control to its owner's hand.

Wayfarer's Bauble

{2}, {T}, Sacrifice this artifact: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Ludevic's Abomination

Ludevic's Test Subject

Defender
{1}{U}: Put a hatchling counter on this creature. Then if there are five or more hatchling counters on it, remove all of them and transform it.

Ludevic's Test Subject // Ludevic's Abomination

Repulse

Return target creature to its owner's hand.
Draw a card.

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.

Lat-Nam Adept

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.