Hooded Blightfang

Deathtouch
Whenever a creature you control with deathtouch attacks, each opponent loses 1 life and you gain 1 life.
Whenever a creature you control with deathtouch deals damage to a planeswalker, destroy that planeswalker.

Caustic Bronco

Whenever this creature attacks, reveal the top card of your library and put it into your hand. You lose life equal to that card's mana value if this creature isn't saddled. Otherwise, each opponent loses that much life.
Saddle 3 (Tap any number of other creatures you control with total power 3 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Orochi Merge-Keeper

{T}: Add {G}.
As long as this creature is modified, it has "{T}: Add {G}{G}." (Equipment, Auras you control, and counters are modifications.)

Tangle Asp

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

Sakura-Tribe Elder

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

Rottenmouth Viper

As an additional cost to cast this spell, you may sacrifice any number of nonland permanents. This spell costs {1} less to cast for each permanent sacrificed this way.
Whenever this creature enters or attacks, put a blight counter on it. Then for each blight counter on it, each opponent loses 4 life unless that player sacrifices a nonland permanent of their choice or discards a card.

Seshiro the Anointed

Other Snake creatures you control get +2/+2.
Whenever a Snake you control deals combat damage to a player, you may draw a card.

Sachi, Daughter of Seshiro

Other Snake creatures you control get +0/+1.
Shamans you control have "{T}: Add {G}{G}."

Aphelia, Viper Whisperer

Deathtouch
Whenever Aphelia attacks, you may pay {1}{B/G}. If you do, create a 1/1 black Snake creature token with deathtouch.
{4}{B}: Until end of turn, whenever one or more Gorgons and/or Snakes you control deal combat damage to a player, that player loses half their life, rounded up.

Stonecoil Serpent

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

Sakura-Tribe Scout

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

Snake Pit

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

Ohran Viper

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

Sidisi, Regent of the Mire

{T}, Sacrifice a creature you control with mana value X other than Sidisi: Return target creature card with mana value X plus 1 from your graveyard to the battlefield. Activate only as a sorcery.

Ikra Shidiqi, the Usurper

Menace
Whenever a creature you control deals combat damage to a player, you gain life equal to that creature's toughness.
Partner (You can have two commanders if both have partner.)