Dabble in Darkness (Red)

When this attacks, banish the top card of your deck. This gets -X

, where X is the pitch value of the card banished this way.

Blood Debt

Rulings

From the Dusk till Dawn release notes

If the card banished has no pitch value, X is 0.
If your deck is empty or you otherwise don’t banish a card this way, X is 0.

Keyword notes

Blood Debt - Blood Debt is a new keyword existing on Shadow cards. Shadow cards can inflict a loss of life to access a greater power. At the end of your turn, you lose 1{h} for each blood debt card in your banished zone.

You only lose life at the end phase. Players do not have priority during the end phase.
If you have multiple cards with blood debt, you lose 1 for each instance of blood debt at the end of turn.
Only face-up cards banished with blood debt counts and will lose you . Face-down banished cards have no effects or stats.