Obelisk of Urd

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.)
As Obelisk of Urd enters, choose a creature type.
Creatures you control of the chosen type get +2/+2.

Skyshroud Claim

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

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Snake Pit

Whenever an opponent casts a blue or black spell, you may create a 1/1 green Snake creature token.

Patron of the Orochi

Snake offering (You may cast this spell any time you could cast an instant by sacrificing a Snake and paying the difference in mana costs between this and the sacrificed Snake. Mana cost includes color.)
{T}: Untap all Forests and all green creatures. Activate only once each turn.

Ophidian

Whenever Ophidian attacks and isn't blocked, you may draw a card. If you do, Ophidian assigns no combat damage this turn.

Giant Growth

Target creature gets +3/+3 until end of turn.

One with Nature

Enchant creature
Whenever enchanted creature deals combat damage to a player, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Sword of the Animist

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {2}

Oran-Rief, the Vastwood

Oran-Rief, the Vastwood enters tapped.
{T}: Add {G}.
{T}: Put a +1/+1 counter on each green creature that entered this turn.

Hinterland Harbor

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

Succumb to Temptation

Sea-Dasher Octopus

Mutate {1}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Flash
Whenever this creature deals combat damage to a player, draw a card.

Honored Hydra

Trample
Embalm {3}{G} ({3}{G}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a white Zombie Snake Hydra with no mana cost. Embalm only as a sorcery.)

Sakura-Tribe Scout

{T}: You may put a land card from your hand onto the battlefield.

Combat Research

Enchant creature
Enchanted creature has "Whenever this creature deals combat damage to a player, draw a card."
As long as enchanted creature is legendary, it gets +1/+1 and has ward {1}. (Whenever enchanted creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)

Acquisition Octopus

Whenever Acquisition Octopus or equipped creature deals combat damage to a player, draw a card.
Reconfigure {2} ({2}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

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.

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.

Sivriss, Nightmare Speaker

{T}, Sacrifice another creature or an artifact: For each opponent, you mill a card, then return that card from your graveyard to your hand unless that player pays 3 life. (To mill a card, put the top card of your library into your graveyard.)
Choose a Background (You can have a Background as a second commander.)

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Leyline of Anticipation

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield.
You may cast spells as though they had flash.

Lorescale Coatl

Whenever you draw a card, put a +1/+1 counter on Lorescale Coatl.

Ribbon Snake

Flying
{2}: Ribbon Snake loses flying until end of turn. Any player may activate this ability.

Beastmaster Ascension

Whenever a creature you control attacks, you may put a quest counter on Beastmaster Ascension.
As long as Beastmaster Ascension has seven or more quest counters on it, creatures you control get +5/+5.

Ancient Craving

You draw three cards and you lose 3 life.

Rogue's Gloves

Whenever equipped creature deals combat damage to a player, you may draw a card.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Tangle Asp

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

Sword of Light and Shadow

Equipped creature gets +2/+2 and has protection from white and from black.
Whenever equipped creature deals combat damage to a player, you gain 3 life and you may return up to one target creature card from your graveyard to your hand.
Equip {2}

Voidslime

Counter target spell, activated ability, or triggered ability. (Mana abilities can't be targeted.)

Naturalize

Elven Chorus

You may look at the top card of your library any time.
You may cast creature spells from the top of your library.
Creatures you control have "{T}: Add one mana of any color."

Minions' Murmurs

You draw X cards and you lose X life, where X is the number of creatures you control.

Painful Truths

Converge — You draw X cards and you lose X life, where X is the number of colors of mana spent to cast this spell.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Stonecoil Serpent

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

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Sylvan Anthem

Green creatures you control get +1/+1.
Whenever a green creature you control enters, scry 1.

Crypt Cobra

Whenever Crypt Cobra attacks and isn't blocked, defending player gets a poison counter. (A player with ten or more poison counters loses the game.)

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.

Kaseto, Orochi Archmage

{G}{U}: Target creature can't be blocked this turn. If that creature is a Snake, it gets +2/+2 until end of turn.

Kindred Discovery

As Kindred Discovery enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

Saw It Coming

Counter target spell.
Foretell {1}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.

Quick Study

Wilderness Reclamation

At the beginning of your end step, untap all lands you control.

Neurok Stealthsuit

Equipped creature has shroud. (It can't be the target of spells or abilities.)
{U}{U}: Attach Neurok Stealthsuit to target creature you control.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Alpha Status

Enchant creature
Enchanted creature gets +2/+2 for each other creature on the battlefield that shares a creature type with it.

Orochi Ranger

Whenever Orochi Ranger deals combat damage to a creature, tap that creature and it doesn't untap during its controller's next untap step.

Family's Favor

Whenever you attack, put a shield counter on target attacking creature. Until end of turn, it gains "Whenever this creature deals combat damage to a player, remove a shield counter from it. If you do, draw a card." (If a creature with a shield counter on it would be dealt damage or destroyed, remove a shield counter from it instead.)

Harmonize

Coiling Oracle

When Coiling Oracle enters, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put that card into your hand.

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

Thornwood Falls

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {G} or {U}.

Gaea's Gift

Put a +1/+1 counter on target creature you control. It gains reach, trample, hexproof, and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Serpent Generator

{4}, {T}: Create a 1/1 colorless Snake artifact creature token. It has "Whenever this creature deals damage to a player, that player gets a poison counter." (A player with ten or more poison counters loses the game.)

Reconnaissance Mission

Whenever a creature you control deals combat damage to a player, you may draw a card.
Cycling {2} ({2}, Discard this card: Draw a card.)

Bamboo Grove Archer

Defender, reach
Channel — {4}{G}, Discard Bamboo Grove Archer: Destroy target creature with flying.

Bone Sabres

Whenever equipped creature attacks, put four +1/+1 counters on it.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Decree of Pain

Destroy all creatures. They can't be regenerated. Draw a card for each creature destroyed this way.
Cycling {3}{B}{B} ({3}{B}{B}, Discard this card: Draw a card.)
When you cycle Decree of Pain, all creatures get -2/-2 until end of turn.

Sword of Hours

Whenever equipped creature attacks, put a +1/+1 counter on it.
Whenever equipped creature deals combat damage, roll a d12. If the result is greater than the damage dealt or the result is 12, double the number of +1/+1 counters on that creature.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Mystic Snake

Flash
When Mystic Snake enters, counter target spell.

Keep Safe

Counter target spell that targets a permanent you control.
Draw a card.

Ohran Frostfang

Attacking creatures you control have deathtouch.
Whenever a creature you control deals combat damage to a player, draw a card.

Yuan-Ti Malison

Yuan-Ti Malison can't be blocked as long as it's attacking alone.
Whenever Yuan-Ti Malison deals combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Simic Signet

Wasteland Viper

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

Prevent all combat damage that would be dealt this turn.

Marsh Boa

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Marsh Viper

Whenever Marsh Viper deals damage to a player, that player gets two poison counters. (A player with ten or more poison counters loses the game.)

Zendikar Resurgent

Whenever you tap a land for mana, add one mana of any type that land produced. (The types of mana are white, blue, black, red, green, and colorless.)
Whenever you cast a creature spell, draw a card.

Keen Sense

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Anaconda

Negate

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

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.

Miscalculation

Counter target spell unless its controller pays {2}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Krosan Constrictor

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{T}: Target black creature gets -2/-0 until end of turn.

Broodbirth Viper

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Whenever Broodbirth Viper deals combat damage to a player, you may draw a card.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Yuan-Ti Fang-Blade

Deathtouch
Whenever Yuan-Ti Fang-Blade deals combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Sign in Blood

Target player draws two cards and loses 2 life.

Pharika's Chosen

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Sol Ring

Raise the Palisade

Choose a creature type. Return all creatures that aren't of the chosen type to their owners' hands.

Mold Adder

Whenever an opponent casts a blue or black spell, you may put a +1/+1 counter on this 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.

Gruesome Realization

Choose one —
• You draw two cards and you lose 2 life.
• Creatures your opponents control get -1/-1 until end of turn.

Return to Nature

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Exile target card from a graveyard.

Ukud Cobra

Soulcoil Viper

{B}, {T}, Sacrifice Soulcoil Viper: Return target creature card from your graveyard to the battlefield with a finality counter on it. Activate only as a sorcery. (If a creature with a finality counter on it would die, exile it instead.)

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Biomass Mutation

Creatures you control have base power and toughness X/X until end of turn.

Dream Fracture

Counter target spell. Its controller draws a card.
Draw a card.

Blackblade Reforged

Equipped creature gets +1/+1 for each land you control.
Equip legendary creature {3}
Equip {7}

Archelos, Lagoon Mystic

As long as Archelos, Lagoon Mystic is tapped, other permanents enter tapped.
As long as Archelos is untapped, other permanents enter untapped.

Mystery Key

When equipped creature deals combat damage to a player, sacrifice Mystery Key. If you do, draw three cards.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Double Major

Copy target creature spell you control, except it isn't legendary if the spell is legendary. (A copy of a creature spell becomes a token.)

Bred for the Hunt

Whenever a creature you control with a +1/+1 counter on it deals combat damage to a player, you may draw a card.

Mark of Sakiko

Enchant creature
Enchanted creature has "Whenever this creature deals combat damage to a player, add that much {G}. Until end of turn, you don't lose this mana as steps and phases end."

Explosive Vegetation

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