Queen's Agent is a common Creature — Vampire Scout card from The List (PLST), collector number XLN-114. Current market price: $0.15, TCGplayer market prices via Scryfall.
Lifelink When this creature enters, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)