At the beginning of each upkeep, if you control no Snakes, create a 1/1 black Snake creature token with deathtouch.

Whenever another creature you control dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.) At the beginning of your upkeep, return target creature card from your graveyard to the battlefield. At the beginning of each opponent's upkeep, that player sacrifices a creature.

At the beginning of your upkeep, you lose 1 life and create a 1/1 black Faerie Rogue creature token with flying.