Contentious Plan

Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Draw a card.

Patagia Viper

Flying
When Patagia Viper enters, create two 1/1 green and blue Snake creature tokens.
When Patagia Viper enters, sacrifice it unless {U} was spent to cast it.

Caravan Vigil

Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Morbid — You may put that card onto the battlefield instead of putting it into your hand if a creature died this turn.

Serpentine Ambush

Until end of turn, target creature becomes a blue Serpent with base power and toughness 5/5.

Negate

Lair of the Hydra

If you control two or more other lands, Lair of the Hydra enters tapped.
{T}: Add {G}.
{X}{G}: Until end of turn, Lair of the Hydra becomes an X/X green Hydra creature. It's still a land. X can't be 0.

Island

Forest

Pendelhaven

{T}: Add {G}.
{T}: Target 1/1 creature gets +1/+2 until end of turn.

Sosuke's Summons

Create two 1/1 green Snake creature tokens.
Whenever a nontoken Snake you control enters, you may return Sosuke's Summons from your graveyard to your hand.

Harmonize

Sol Ring

Blight Mamba

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{1}{G}: Regenerate Blight Mamba.

Hornet Cobra

Divination

Ambush Viper

Hardened Scales

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

Rhonas's Last Stand

Create a 5/4 green Snake creature token. Lands you control don't untap during your next untap step.

Quest for Ula's Temple

At the beginning of your upkeep, you may look at the top card of your library. If it's a creature card, you may reveal it and put a quest counter on Quest for Ula's Temple.
At the beginning of each end step, if there are three or more quest counters on Quest for Ula's Temple, you may put a Kraken, Leviathan, Octopus, or Serpent creature card from your hand onto the battlefield.

Broken Bond

Destroy target artifact or enchantment. You may put a land card from your hand onto the battlefield.

Narnam Cobra

{G}: Narnam Cobra gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy it.)

Saheeli's Silverwing

Flying
When Saheeli's Silverwing enters, look at the top card of target opponent's library.

Explore

You may play an additional land this turn.
Draw a card.

Skullwinder

Deathtouch
When Skullwinder enters, return target card from your graveyard to your hand, then choose an opponent. That player returns a card from their graveyard to their hand.

Destructor Dragon

Flying
When Destructor Dragon dies, destroy target noncreature permanent.

Botanical Sanctum

Botanical Sanctum enters tapped unless you control two or fewer other lands.
{T}: Add {G} or {U}.

Tanglepool Bridge

Tanglepool Bridge enters tapped.
Indestructible
{T}: Add {G} or {U}.

Death-Hood Cobra

{1}{G}: Death-Hood Cobra gains reach until end of turn.
{1}{G}: Death-Hood Cobra gains deathtouch until end of turn.

Wasteland Viper

Deathtouch
Bloodrush — {G}, Discard Wasteland Viper: Target attacking creature gets +1/+2 and gains deathtouch until end of turn.

Thornwood Falls

Thornwood Falls enters tapped.
When Thornwood Falls enters, you gain 1 life.
{T}: Add {G} or {U}.

Skyline Cascade

Skyline Cascade enters tapped.
When Skyline Cascade enters, target creature an opponent controls doesn't untap during its controller's next untap step.
{T}: Add {U}.

Koma, Cosmos Serpent

This spell can't be countered.
At the beginning of each upkeep, create a 3/3 blue Serpent creature token named Koma's Coil.
Sacrifice another Serpent: Choose one —
• Tap target permanent. Its activated abilities can't be activated this turn.
• Koma, Cosmos Serpent gains indestructible until end of turn.

Quandrix Command

Choose two —
• Return target creature or planeswalker to its owner's hand.
• Counter target artifact or enchantment spell.
• Put two +1/+1 counters on target creature.
• Target player shuffles up to three target cards from their graveyard into their library.

Living Artifact

Enchant artifact
Whenever you're dealt damage, put that many vitality counters on Living Artifact.
At the beginning of your upkeep, you may remove a vitality counter from Living Artifact. If you do, you gain 1 life.

Ramunap Hydra

Vigilance, reach, trample
Ramunap Hydra gets +1/+1 as long as you control a Desert.
Ramunap Hydra gets +1/+1 as long as there is a Desert card in your graveyard.

Hinterland Harbor

Hinterland Harbor enters tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Wind Zendikon

Enchant land
Enchanted land is a 2/2 blue Elemental creature with flying. It's still a land.
When enchanted land dies, return that card to its owner's hand.

Coiling Stalker

Ninjutsu {1}{G} ({1}{G}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Coiling Stalker deals combat damage to a player, put a +1/+1 counter on target creature you control that doesn't have a +1/+1 counter on it.

Tangle Asp

Whenever Tangle Asp blocks or becomes blocked by a creature, destroy that creature at end of combat.

Ohran Viper

Whenever Ohran Viper deals combat damage to a creature, destroy that creature at end of combat.
Whenever Ohran Viper deals combat damage to a player, you may draw a card.

Verazol, the Split Current

Verazol, the Split Current enters with a +1/+1 counter on it for each mana spent to cast it.
Whenever you cast a kicked spell, you may remove two +1/+1 counters from Verazol. If you do, copy that spell. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

Lotus Cobra

Landfall — Whenever a land you control enters, add one mana of any color.

Boneyard Wurm

Boneyard Wurm's power and toughness are each equal to the number of creature cards in your graveyard.

Second Harvest

For each token you control, create a token that's a copy of that permanent.

Moss Viper

Cosmic Hunger

Target creature you control deals damage equal to its power to another target creature, planeswalker, or battle.

Fang of Shigeki

Seed the Land

Whenever a land enters, its controller creates a 1/1 green Snake creature token.

Druidic Ritual

You may mill three cards. Then return up to one creature card and up to one land card from your graveyard to your hand. (To mill a card, put the top card of your library into your graveyard.)

Brainstone

{2}, {T}, Sacrifice Brainstone: Draw three cards, then put two cards from your hand on top of your library in any order.

Gretchen Titchwillow

{2}{G}{U}: Draw a card. You may put a land card from your hand onto the battlefield.

Hexdrinker

Level up {1} ({1}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 3-7
4/4
Protection from instants
LEVEL 8+
6/6
Protection from everything

Winged Coatl

Flash (You may cast this spell any time you could cast an instant.)
Flying
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Snake Basket

{X}, Sacrifice Snake Basket: Create X 1/1 green Snake creature tokens. Activate only as a sorcery.

Counterspell

Crop Sigil

At the beginning of your upkeep, you may mill a card.
Delirium — {2}{G}, Sacrifice Crop Sigil: Return up to one target creature card and up to one target land card from your graveyard to your hand. Activate only if there are four or more card types among cards in your graveyard.

Llanowar Reborn

Llanowar Reborn enters tapped.
{T}: Add {G}.
Graft 1 (This land enters with a +1/+1 counter on it. Whenever a creature enters, you may move a +1/+1 counter from this land onto it.)

Aetherize

Return all attacking creatures to their owner's hand.

Nissa's Pilgrimage

Search your library for up to two basic Forest cards, reveal those cards, and put one onto the battlefield tapped and the rest into your hand. Then shuffle.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, search your library for up to three basic Forest cards instead of two.

Stonecoil Serpent

Reach, trample, protection from multicolored
Stonecoil Serpent enters with X +1/+1 counters on it.

Rampant Growth

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