Ethereal Ambush is a common Instant card from The List (PLST), collector number FRF-152. Current market price: $0.40, TCGplayer market prices via Scryfall.
Manifest the top two cards of your library. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)