Universal Automaton

Changeling (This card is every creature type.)

Fang Skulkin

{2}: Target black creature gains wither until end of turn. (It deals damage to creatures in the form of -1/-1 counters.)

Simic Signet

Manalith

Watchwing Scarecrow

Watchwing Scarecrow has vigilance as long as you control a white creature.
Watchwing Scarecrow has flying as long as you control a blue creature.

Explosive Vegetation

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Wicker Warcrawler

Whenever Wicker Warcrawler attacks or blocks, put a -1/-1 counter on it at end of combat.

Antler Skulkin

{2}: Target white creature 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.)

Shell Skulkin

{3}: Target blue creature gains shroud until end of turn. (It can't be the target of spells or abilities.)

Hoof Skulkin

{3}: Target green creature gets +1/+1 until end of turn.

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Birthing Boughs

{4}, {T}: Create a 2/2 colorless Shapeshifter creature token with changeling. (It has every creature type.)

Irregular Cohort

Changeling (This card is every creature type.)
When Irregular Cohort enters the battlefield, create a 2/2 colorless Shapeshifter creature token with changeling.

Mirror March

Whenever a nontoken creature enters the battlefield under your control, flip a coin until you lose a flip. For each flip you won, create a token that's a copy of that creature. Those tokens gain haste. Exile them at the beginning of the next end step.

Jawbone Skulkin

{2}: Target red creature gains haste until end of turn.

Quasiduplicate

Create a token that's a copy of target creature you control.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Selesnya Signet

Spark Double

You may have Spark Double enter the battlefield as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

Spitting Image

Create a token that's a copy of target creature.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Tatterkite

Flying
Tatterkite can't have counters put on it.

Wingrattle Scarecrow

Wingrattle Scarecrow has flying as long as you control a blue creature.
Wingrattle Scarecrow has persist as long as you control a black creature. (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.)

Farmstead Gleaner

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

Jousting Dummy

{3}: Jousting Dummy gets +1/+0 until end of turn.

Blazethorn Scarecrow

Blazethorn Scarecrow has haste as long as you control a red creature.
Blazethorn Scarecrow has wither as long as you control a green creature. (It deals damage to creatures in the form of -1/-1 counters.)

Soulherder

Whenever a creature is exiled from the battlefield, put a +1/+1 counter on Soulherder.
At the beginning of your end step, you may exile another target creature you control, then return that card to the battlefield under its owner's control.

Golgari Signet

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Rattleblaze Scarecrow

Rattleblaze Scarecrow has persist as long as you control a black creature. (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.)
Rattleblaze Scarecrow has haste as long as you control a red creature.

Ephemerate

Exile target creature you control, then return it to the battlefield under its owner's control.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Field Creeper

Dimir Signet

Scrapbasket

{1}: Scrapbasket becomes all colors until end of turn.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Reaper King

({2/W} can be paid with any two mana or with {W}. This card's mana value is 10.)
Other Scarecrow creatures you control get +1/+1.
Whenever another Scarecrow enters the battlefield under your control, destroy target permanent.

Signpost Scarecrow

Vigilance
{2}: Add one mana of any color.

Izzet Signet

Mirrorworks

Whenever another nontoken artifact enters the battlefield under your control, you may pay {2}. If you do, create a token that's a copy of that artifact.

Scaretiller

Whenever Scaretiller becomes tapped, choose one —
• You may put a land card from your hand onto the battlefield tapped.
• Return target land card from your graveyard to the battlefield tapped.

Azorius Signet

Wild-Field Scarecrow

Defender
{2}, Sacrifice Wild-Field Scarecrow: Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.

Chainbreaker

Chainbreaker enters the battlefield with two -1/-1 counters on it.
{3}, {T}: Remove a -1/-1 counter from target creature.

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

One-Eyed Scarecrow

Defender
Creatures with flying your opponents control get -1/-0.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Circuitous Route

Search your library for up to two basic land cards and/or Gate cards, put them onto the battlefield tapped, then shuffle.

Changeling Hero

Changeling (This card is every creature type.)
Champion a creature (When this enters the battlefield, sacrifice it unless you exile another creature you control. When this leaves the battlefield, that card returns to the battlefield.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Scuttlemutt

{T}: Add one mana of any color.
{T}: Target creature becomes the color or colors of your choice until end of turn.

Eerie Interlude

Exile any number of target creatures you control. Return those cards to the battlefield under their owner's control at the beginning of the next end step.

Orzhov Signet

Heap Doll

Sacrifice Heap Doll: Exile target card from a graveyard.

Changeling Berserker

Changeling (This card is every creature type.)
Haste
Champion a creature (When this enters the battlefield, sacrifice it unless you exile another creature you control. When this leaves the battlefield, that card returns to the battlefield.)

Unsettled Mariner

Changeling (This card is every creature type.)
Whenever you or a permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {1}.

Pillar of Origins

As Pillar of Origins enters the battlefield, choose a creature type.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Gruul Signet

Mirrormade

You may have Mirrormade enter the battlefield as a copy of any artifact or enchantment on the battlefield.

Shard Convergence

Search your library for a Plains card, an Island card, a Swamp card, and a Mountain card. Reveal those cards, put them into your hand, then shuffle.

Scrounged Scythe

Equipped creature gets +1/+1.
As long as equipped creature is a Human, it has menace. (It can't be blocked except by two or more creatures.)
Equip {2}

Harvest Hand

When Harvest Hand dies, return it to the battlefield transformed under your control.

Harvest Hand // Scrounged Scythe

Lurebound Scarecrow

As Lurebound Scarecrow enters the battlefield, choose a color.
When you control no permanents of the chosen color, sacrifice Lurebound Scarecrow.