Protean Hydra

This creature enters with X +1/+1 counters on it.
If damage would be dealt to this creature, prevent that damage and remove that many +1/+1 counters from it.
Whenever a +1/+1 counter is removed from this creature, put two +1/+1 counters on it at the beginning of the next end step.

Have

Esika's Chariot

When Esika's Chariot enters, create two 2/2 green Cat creature tokens.
Whenever Esika's Chariot attacks, create a token that's a copy of target token you control.
Crew 4

Dryad of the Ilysian Grove

You may play an additional land on each of your turns.
Lands you control are every basic land type in addition to their other types.

Recon Craft Theta

Flying
When this Vehicle enters, create a 0/0 blue Alien creature token. Put a +1/+1 counter on it.
Whenever this Vehicle attacks, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Crew 2

Quilled Greatwurm

Trample
Whenever a creature you control deals combat damage during your turn, put that many +1/+1 counters on it. (It must survive to get the counters.)
You may cast this card from your graveyard by removing six counters from among creatures you control in addition to paying its other costs.

Prismatic Omen

Lands you control are every basic land type in addition to their other types.

Etched Oracle

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)
{1}, Remove four +1/+1 counters from this creature: Target player draws three cards.

Hopeful Initiate

Training (Whenever this creature attacks with another creature with greater power, put a +1/+1 counter on this creature.)
{2}{W}, Remove two +1/+1 counters from among creatures you control: Destroy target artifact or enchantment.

Mossbridge Troll

If this creature would be destroyed, regenerate it.
Tap any number of untapped creatures you control other than this creature with total power 10 or greater: This creature gets +20/+20 until end of turn.

Hydra Trainer

You may exert this creature as it attacks. When you do, target creature gets +X/+X until end of turn, where X is the number of counters on permanents you control. (An exerted creature won't untap during your next untap step.)
{2}{G}: Adapt 2. (If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.)

Relic of Legends

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

Sanwell, Avenger Ace

As long as an artifact creature you control is attacking, prevent all damage that would be dealt to Sanwell.
Whenever Sanwell becomes tapped, exile the top six cards of your library. You may cast a Vehicle or artifact creature spell from among them. Then put the rest on the bottom of your library in a random order.

Unstable Frontier

{T}: Add {C}.
{T}: Target land you control becomes the basic land type of your choice until end of turn.

Losheel, Clockwork Scholar

Prevent all combat damage that would be dealt to attacking artifact creatures you control.
Whenever one or more artifact creatures you control enter, draw a card. This ability triggers only once each turn.

Cauldron of Souls

{T}: Choose any number of target creatures. Each of those creatures gains persist until end of turn. (When it 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.)

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.

Masako the Humorless

Flash
Tapped creatures you control can block as though they were untapped.

Sigarda's Summons

Creatures you control with +1/+1 counters on them have base power and toughness 4/4, have flying, and are Angels in addition to their other types.

Brigone, Soldier of Meletis

Vigilance
Heroic — Whenever you cast a spell that targets Brigone, put a +1/+1 counter on Brigone.
{T}, Remove a +1/+1 counter from Brigone: Draw a card.

Crystalline Crawler

Converge — This creature enters with a +1/+1 counter on it for each color of mana spent to cast it.
Remove a +1/+1 counter from this creature: Add one mana of any color.
{T}: Put a +1/+1 counter on this creature.

Thunderhawk Gunship

Flying
When this Vehicle enters, create two 2/2 white Astartes Warrior creature tokens with vigilance.
Whenever this Vehicle attacks, attacking creatures you control gain flying until end of turn.
Crew 2

Wylie Duke, Atiin Hero

Vigilance
Whenever Wylie Duke becomes tapped, you gain 1 life and draw a card.

Dominaria's Judgment

Until end of turn, creatures you control gain protection from white if you control a Plains, from blue if you control an Island, from black if you control a Swamp, from red if you control a Mountain, and from green if you control a Forest.

Leyline Binding

Flash
Domain — This spell costs {1} less to cast for each basic land type among lands you control.
When this enchantment enters, exile target nonland permanent an opponent controls until this enchantment leaves the battlefield.

Emmara, Soul of the Accord

Whenever Emmara becomes tapped, create a 1/1 white Soldier creature token with lifelink.

District Mascot

This creature enters with a +1/+1 counter on it.
{1}{G}, Remove two +1/+1 counters from this creature: Destroy target artifact.
Whenever this creature attacks while saddled, put a +1/+1 counter on it.
Saddle 1

Mechtitan Core

{5}, Exile this Vehicle and four other artifact creatures and/or Vehicles you control: Create Mechtitan, a legendary 10/10 Construct artifact creature token with flying, vigilance, trample, lifelink, and haste that's all colors. When that token leaves the battlefield, return all cards exiled with this Vehicle except this card to the battlefield tapped under their owners' control.
Crew 2

Cultivator's Caravan

{T}: Add one mana of any color.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

Fertilid

This creature enters with two +1/+1 counters on it.
{1}{G}, Remove a +1/+1 counter from this creature: Target player searches their library for a basic land card, puts it onto the battlefield tapped, then shuffles.

Legolas's Quick Reflexes

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Untap target creature. Until end of turn, it gains hexproof, reach, and "Whenever this creature becomes tapped, it deals damage equal to its power to up to one target creature."

Keldon Battlewagon

Trample
This creature can't block.
When this creature attacks, sacrifice it at end of combat.
Tap an untapped creature you control: This creature gets +X/+0 until end of turn, where X is the power of the creature tapped this way.

The Prydwen, Steel Flagship

Flying
Whenever another nontoken artifact you control enters, create a 2/2 white Human Knight creature token with "This token gets +2/+2 as long as an artifact entered the battlefield under your control this turn."
Crew 2

Knight Paladin

Trample
Rapid-fire Battle Cannon — When this Vehicle enters, it deals 4 damage to each opponent.
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

Golden Argosy

Whenever Golden Argosy attacks, exile each creature that crewed it this turn. Return them to the battlefield tapped under their owner's control at the beginning of the next end step.
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

Nylea's Presence

Enchant land
When this Aura enters, draw a card.
Enchanted land is every basic land type in addition to its other types.

Navigator's Compass

When this artifact enters, you gain 3 life.
{T}: Until end of turn, target land you control becomes the basic land type of your choice in addition to its other types.

Cid, Freeflier Pilot

Equipment and Vehicle spells you cast cost {1} less to cast.
Jump — During your turn, Cid has flying.
{2}, {T}: Return target Equipment or Vehicle card from your graveyard to your hand.

Thran Portal

This land enters tapped unless you control two or fewer other lands.
As this land enters, choose a basic land type.
This land is the chosen type in addition to its other types.
Mana abilities of this land cost an additional 1 life to activate.

Hierophant Bio-Titan

Frenzied Metabolism — As an additional cost to cast this spell, you may remove any number of +1/+1 counters from among creatures you control. This spell costs {2} less to cast for each counter removed this way.
Vigilance, reach, ward {2}
Titanic — This creature can't be blocked by creatures with power 2 or less.

Zar Ojanen, Scion of Efrava

Domain — Whenever Zar Ojanen becomes tapped, put a +1/+1 counter on each creature you control with toughness less than the number of basic land types among lands you control.

Lush Growth

Enchant land
Enchanted land is a Mountain, Forest, and Plains.

Sol Ring

Harvest Season

Search your library for up to X basic land cards, where X is the number of tapped creatures you control, put those cards onto the battlefield tapped, then shuffle.

Mikaeus, the Lunarch

Mikaeus enters with X +1/+1 counters on it.
{T}: Put a +1/+1 counter on Mikaeus.
{T}, Remove a +1/+1 counter from Mikaeus: Put a +1/+1 counter on each other creature you control.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Benevolent Hydra

This creature enters with X +1/+1 counters on it.
If one or more +1/+1 counters would be put on another creature you control, that many plus one +1/+1 counters are put on it instead.
{T}, Remove a +1/+1 counter from this creature: Put a +1/+1 counter on another target creature you control.

Scholar of New Horizons

This creature enters with a +1/+1 counter on it.
{T}, Remove a counter from a permanent you control: Search your library for a Plains card and reveal it. If an opponent controls more lands than you, you may put that card onto the battlefield tapped. If you don't put the card onto the battlefield, put it into your hand. Then shuffle.

Honor-Worn Shaku

{T}: Add {C}.
Tap an untapped legendary permanent you control: Untap this artifact.

Getting

Veteran Beastrider

At the beginning of your end step, untap each creature you control.
{2}{G}{W}: Creatures you control get +1/+1 until end of turn.

Centaur Omenreader

As long as this creature is tapped, creature spells you cast cost {2} less to cast.

Quest for Renewal

Whenever a creature you control becomes tapped, you may put a quest counter on this enchantment.
As long as there are four or more quest counters on this enchantment, untap all creatures you control during each other player's untap step.

Storm of Souls

Return all creature cards from your graveyard to the battlefield. Each of them is a 1/1 Spirit with flying in addition to its other types. Exile Storm of Souls.

Reveille Squad

Whenever one or more creatures attack you, if this creature is untapped, you may untap all creatures you control.

Sanctuary Warden

Flying
This creature enters with two shield counters on it.
Whenever this creature enters or attacks, you may remove a counter from a creature or planeswalker you control. If you do, draw a card and create a 1/1 green and white Citizen creature token.

Rite of Harmony

Whenever a creature or enchantment you control enters this turn, draw a card.
Flashback {2}{G}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

This creature gets +0/+2 as long as you control a Plains, has flying as long as you control an Island, gets +2/+0 as long as you control a Swamp, has first strike as long as you control a Mountain, and has trample as long as you control a Forest.

Mysterious Limousine

Whenever this Vehicle enters or attacks, exile up to one other target creature until this Vehicle leaves the battlefield. If a creature is put into exile this way, return each other card exiled with this Vehicle to the battlefield under its owner's control.
Crew 2

Order of Whiteclay

{1}{W}{W}, {Q}: Return target creature card with mana value 3 or less from your graveyard to the battlefield. ({Q} is the untap symbol.)

Brightglass Gearhulk

First strike, trample
When this creature enters, you may search your library for up to two artifact, creature, and/or enchantment cards with mana value 1 or less, reveal them, put them into your hand, then shuffle.

Steelbane Hydra

This creature enters with X +1/+1 counters on it.
{2}{G}, Remove a +1/+1 counter from this creature: Destroy target artifact or enchantment.

Salvation Engine

Other artifact creatures you control get +2/+2.
Whenever this Vehicle attacks, return up to one target artifact card from your graveyard to the battlefield.
Crew 6

Nautiloid Ship

Flying
When this Vehicle enters, exile target player's graveyard.
Whenever this Vehicle deals combat damage to a player, you may put a creature card exiled with this Vehicle onto the battlefield under your control.
Crew 3

Skysovereign, Consul Flagship

Flying
Whenever Skysovereign enters or attacks, it deals 3 damage to target creature or planeswalker an opponent controls.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

Branching Evolution

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on that creature instead.

Lulu, Loyal Hollyphant

Flying
At the beginning of your end step, if a permanent you controlled left the battlefield this turn, put a +1/+1 counter on each tapped creature you control, then untap them.
Choose a Background (You can have a Background as a second commander.)

Quicksilver Fountain

At the beginning of each player's upkeep, that player puts a flood counter on target non-Island land they control of their choice. That land is an Island for as long as it has a flood counter on it.
At the beginning of each end step, if all lands on the battlefield are Islands, remove all flood counters from them.

Drumbellower

Flying
Untap all creatures you control during each other player's untap step.

Devout Invocation

Tap any number of untapped creatures you control. Create a 4/4 white Angel creature token with flying for each creature tapped this way.

Caradora, Heart of Alacria

When Caradora enters, you may search your library for a Mount or Vehicle card, reveal it, put it into your hand, then shuffle.
If one or more +1/+1 counters would be put on a creature or Vehicle you control, that many plus one +1/+1 counters are put on it instead.

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.

Illustrious Wanderglyph

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
Other artifact creatures you control get +2/+2 as long as you have the city's blessing.
At the beginning of each upkeep, create a 1/1 colorless Gnome artifact creature token.

Forest

Halo Fountain

{W}, {T}, Untap a tapped creature you control: Create a 1/1 green and white Citizen creature token.
{W}{W}, {T}, Untap two tapped creatures you control: Draw a card.
{W}{W}{W}{W}{W}, {T}, Untap fifteen tapped creatures you control: You win the game.

Twilight Drover

Whenever a creature token leaves the battlefield, put a +1/+1 counter on this creature.
{2}{W}, Remove a +1/+1 counter from this creature: Create two 1/1 white Spirit creature tokens with flying.

Plains

Botanical Brawler

Trample
This creature enters with two +1/+1 counters on it.
Whenever one or more +1/+1 counters are put on another permanent you control, if it's the first time +1/+1 counters have been put on that permanent this turn, put a +1/+1 counter on this creature.

Shinewend

Flying
This creature enters with a +1/+1 counter on it.
{1}{W}, Remove a +1/+1 counter from this creature: Destroy target enchantment.

Overlord of the Hauntwoods

Impending 4—{1}{G}{G} (If you cast this spell for its impending cost, it enters with four time counters and isn't a creature until the last is removed. At the beginning of your end step, remove a time counter from it.)
Whenever this permanent enters or attacks, create a tapped colorless land token named Everywhere that is every basic land type.