Lautrec, Fina's Chosen

Lautrec, Fina's Chosen cannot be blocked
{1}{w}: Tap a creature
{2}{b}: Draw a card
{b}{b} Sacrifice two creatures: Transform this card.
{1}{b}{b}: Target player sacrifices a creature with Fire Keeper and if they do, transform this card.
Activate this effect only as a sorcery.