Biomathematician is a common Creature — Human Wizard card from Strixhaven: School of Mages (STX), collector number 164. Current market price: $0.15 (foil $0.13), TCGplayer market prices via Scryfall.
When this creature enters, create a 0/0 green and blue Fractal creature token. Put a +1/+1 counter on each Fractal you control.