Susan Foreman is a rare Legendary Creature — Time Lord card from Doctor Who (WHO), collector number 400. Current market price: $0.31 (foil $0.35), TCGplayer market prices via Scryfall.
If you would planeswalk, instead look at the top two cards of your planar deck, put one on the bottom of your planar deck and the other on top, then planeswalk. {T}: Add {G}. Doctor's companion (You can have two commanders if the other is the Doctor.)