Aether Vial is a uncommon Artifact card from The List (PLST), collector number DST-91. Current market price: $3.99, TCGplayer market prices via Scryfall.
At the beginning of your upkeep, you may put a charge counter on this artifact. {T}: You may put a creature card with mana value equal to the number of charge counters on this artifact from your hand onto the battlefield.