Skeletal Vampire

Flying
When this creature enters, create two 1/1 black Bat creature tokens with flying.
{3}{B}{B}, Sacrifice a Bat: Create two 1/1 black Bat creature tokens with flying.
Sacrifice a Bat: Regenerate this creature.

RNA Guild Kit

Flying
When Skeletal Vampire enters the battlefield, create two 1/1 black Bat creature tokens with flying.
{3}{B}{B}, Sacrifice a Bat: Create two 1/1 black Bat creature tokens with flying.
Sacrifice a Bat: Regenerate Skeletal Vampire.

Commander 2017

Duel Decks Anthology: Garruk vs. Liliana

Flying
When Skeletal Vampire enters the battlefield, put two 1/1 black Bat creature tokens with flying onto the battlefield.
{3}{B}{B}, Sacrifice a Bat: Put two 1/1 black Bat creature tokens with flying onto the battlefield.
Sacrifice a Bat: Regenerate Skeletal Vampire.

Modern Masters

Duel Decks: Garruk vs. Liliana

Flying
When Skeletal Vampire enters the battlefield, put two 1/1 black Bat creature tokens onto the battlefield.
{3}{B}{B}, Sacrifice a Bat: Put two 1/1 black Bat creature tokens with flying onto the battlefield.
Sacrifice a Bat: Regenerate Skeletal Vampire.

You may pay the cost of Skeletal Vampire's activated abilities by sacrificing any Bat, not just a Bat token it created.