Berseria

{b}: Berseria gets deathtouch until end of turn.
{b}{g}: Target creature gets deathtouch until
end of turn.
{1}{b}{b/g}{t}: As an additional cost to cast this
ability, sacrifice a creature. Berseria deals damage
equal to its strength.
{2}{b}{g}: Until end of turn when a creature under
your control with deathtouch deals damage to a opponent, that player loses the game.