Arina, Venomous Assassin

Infect, Deathtouch
{x}{b/g} Put a 2/2 green/black Ethereal Serpent token with death touch onto the battlefield under your control.
{t}{b/g}{b/g} Ethereal Serpents you control gain skulk.
When Arina dies, put a 4/4 green/black creature named "Silas, Serpent Spirit" onto the battlefield under your control. It has deathtouch and infect.