Star of Mathematical Excellence

Adric won a badge for "mathematical excellence". (TV: Full Circle) It was fashioned in a star shape with gold edges. The Fifth Doctor used this badge to kill a Cyber-Leader within the TARDIS control room; by crushing the badge into its chest unit, the Doctor suffocated the Cyberman before shooting it with a Cyber-gun. (TV: Earthshock)

Later, when the Xeraphin used an image of Adric to try and trick Nyssa and Tegan Jovanka, the badge was intact. This is how Nyssa and Tegan knew that "Adric" was not real. (TV: Time-Flight)

Behind the scenes

 * In recognition of his death, the closing credits of Earthshock rolled in silence over the broken pieces of Adric's badge.