Peri Brown is a rare Legendary Creature — Human card from Doctor Who (WHO), collector number 344. Current market price: $0.36 (foil $0.77), TCGplayer market prices via Scryfall.
The first historic spell you cast each turn has convoke. (Your creatures can help cast it. Each creature you tap while casting it pays for {1} or one mana of that creature's color.) Doctor's companion (You can have two commanders if the other is the Doctor.)