Penelope Platypus

Penelope Platypus is a member of the Substitute Freedom Fighters from Downunda. Penelope was one of several Freedom Fighters recruits chosen by Sally Acorn for a special mission meant to determine their potential. The mission resulted in the uncovering of Dr. Ivo Robotnik's Auto Atomatons, a scheme that the Substitute Freedom Fighters, aided by Geoffrey St. John, were able to thwart.

Penelope and the others would later come to the aid of Sally and her more experienced squad on several occasions, including stopping an amnesia-ridden Sonic from defeating the Knothole Freedom Fighters, a bizarre conflict involving a video-game link between Mobius and Earth, and a period of time in which Sonic was bereft of his speed and had to rescue the Knothole Freedom Fighters from captivity.

Two years later, Penelope would later be elected to serve on the Council of Acorn.