You have at least three other cards in your graveyard.
Mana Needed
({2} magic symbol) ({B} magic symbol) available.
Steps
Cast
Priest of Gix from your graveyard for its escape cost by paying ({2} magic symbol) ({B} magic symbol) and exiling three other cards from your graveyard.
Priest of Gix enters the battlefield, adding ({B} magic symbol) ({B} magic symbol) ({B} magic symbol) .
Activate
Lord of the Forsaken's first ability by paying ({B} magic symbol) and sacrificing
Priest of Gix.
Priest of Gix dies, triggering
Dross Harvester, causing you to gain two life.
Resolve the
Lord of the Forsaken ability, causing you to mill three cards.
Activate
Lord of the Forsaken's second ability by paying 1 life, adding ({C} magic symbol) that can only be spent to cast spells from your graveyard.