Avatar of Woe is a mythic Creature — Avatar card from Conspiracy: Take the Crown (CN2), collector number 128. Current market price: $4.03 (foil $10.12), TCGplayer market prices via Scryfall.
If there are ten or more creature cards total in all graveyards, this spell costs {6} less to cast. Fear (This creature can't be blocked except by artifact creatures and/or black creatures.) {T}: Destroy target creature. It can't be regenerated.