At the beginning of your end step, if you gained life this turn, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")
Sacrifice two Blood tokens: Transform this creature. Activate only as a sorcery.

At the beginning of your end step, if you gained life this turn, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")
{4}{B}: Each opponent loses 2 life and you gain 2 life.