Cement Shoes

Equipped creature gets +3/+3 and has "At the beginning of your end step, tap this creature."
Equipped creature doesn't untap during its controller's untap step.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Aspect of Hydra

Target creature gets +X/+X until end of turn, where X is your devotion to green. (Each {G} in the mana costs of permanents you control counts toward your devotion to green.)

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.)

Ohran Frostfang

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

Lavaspur Boots

Equipped creature gets +1/+0 and has haste and ward {1}. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)
Equip {1}

Sabertooth Cobra

Whenever Sabertooth Cobra deals damage to a player, that player gets a poison counter. The player gets another poison counter at the beginning of their next upkeep unless they pay {2} before that step. (A player with ten or more poison counters loses the game.)

Stonecoil Serpent

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

Noose Constrictor

Reach
Discard a card: Noose Constrictor gets +1/+1 until end of turn.

Hornet Cobra

Coiled Tinviper

Nafs Asp

Whenever Nafs Asp deals damage to a player, that player loses 1 life at the beginning of their next draw step unless they pay {1} before that draw step.

Fleetfeather Sandals

Equipped creature has flying and haste.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Wasteland Viper

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

Snake Umbra

Enchant creature
Enchanted creature gets +1/+1 and has "Whenever this creature deals damage to an opponent, you may draw a card."
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Lightning Greaves

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

Zephyr Boots

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

Nemesis of Mortals

This spell costs {1} less to cast for each creature card in your graveyard.
{7}{G}{G}: Monstrosity 5. This ability costs {1} less to activate for each creature card in your graveyard. (If this creature isn't monstrous, put five +1/+1 counters on it and it becomes monstrous.)

Serpent Skin

Flash
Enchant creature
Enchanted creature gets +1/+1.
{G}: Regenerate enchanted creature.

Serpent's Gift

Target creature gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy it.)

Voracious Typhon

Escape—{5}{G}{G}, Exile four other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Voracious Typhon escapes with three +1/+1 counters on it.

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.)

Ambush Viper

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

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.)

Moss Viper

Snake Pit

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

Cobra Trap

If a noncreature permanent under your control was destroyed this turn by a spell or ability an opponent controlled, you may pay {G} rather than pay this spell's mana cost.
Create four 1/1 green Snake creature tokens.

Marsh Boa

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

Glass Asp

Whenever Glass Asp deals combat damage to a player, that player loses 2 life at the beginning of their next draw step unless they pay {2} before that step.

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.

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.

Ankle Biter

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.

Snake of the Golden Grove

Tribute 3 (As this creature enters the battlefield, an opponent of your choice may put three +1/+1 counters on it.)
When Snake of the Golden Grove enters the battlefield, if tribute wasn't paid, you gain 4 life.

Skullwinder

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

Mire Boa

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{G}: Regenerate Mire Boa. (The next time this creature would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)

Jewel-Eyed Cobra

Deathtouch
When Jewel-Eyed Cobra dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Boa Constrictor

{T}: Boa Constrictor gets +3/+3 until end of turn.

Feiyi Snake

Reach (This creature can block creatures with flying.)

Trailblazer's Boots

Equipped creature has nonbasic landwalk. (It can't be blocked as long as defending player controls a nonbasic land.)
Equip {2}

Tangle Asp

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

River Boa

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
{G}: Regenerate River Boa.

Tower Winder

Reach, deathtouch
When Tower Winder enters the battlefield, search your library and/or graveyard for a card named Command Tower, reveal it, and put it into your hand. If you search your library this way, shuffle.

Nessian Asp

Reach
{6}{G}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)