Judge Unworthy is a common Instant card from Time Spiral Remastered (TSR), collector number 21. Current market price: $0.26 (foil $0.40), TCGplayer market prices via Scryfall.
Choose target attacking or blocking creature. Scry 3, then reveal the top card of your library. Judge Unworthy deals damage equal to that card's mana value to that creature.