Sahrah, seer of cycle

X: sacrifice X permanents or discard X cars and put X cards from the top of your library in the graveyard
0: draw X cards where X is the number of cards in your grave, then exile all cards in your graveyard and discard cards until left 7 in your hand
-X: cast X cards from your exile without paying it's costs, than return the rest of the exiled cards to your grave and gain half X life rpunded up