The Mechanist, Aerial Artisan is a rare Legendary Creature — Human Artificer Ally card from Avatar: The Last Airbender (TLA), collector number 64. Current market price: $0.24 (foil $0.33), TCGplayer market prices via Scryfall.
Whenever you cast a noncreature spell, create a Clue token. (It's an artifact with "{2}, Sacrifice this token: Draw a card.") {T}: Until end of turn, target artifact token you control becomes a 3/1 Construct artifact creature with flying.