Kharenthas, Blood Initiate

Lifelink
When this creature enters the battlefield, you
may search your library for a Demon card with converted mana cost 5 or less, put it into your
graveyard, then shuffle your library
{5}{b}{b}{b}, pay 4 life, sacrifice a creature: Return Kharenthas, Blood Initiate from your graveyard
to the battlefield transformed under your control