The Final Days

Create two tapped 2/2 black Horror creature tokens. If this spell was cast from a graveyard, instead create X of those tokens, where X is the number of creature cards in your graveyard. Flashback {4}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

From Magic: The Gathering.

Open the interactive version on https://mythscribe.cloud/app/tcg/cards/cms6ol0cjf8r7pb1hodyijwwj.