Spring-Heeled Jack (バネ足ジャック Baneashijakku, born 29 April), otherwise known as Evil or Anti Spectrum (イービル/アンチスペクトラム Ībiru/ anchisupekutoramu), is a character in the Rookie Chronicles. In an alternate timeline branching off from Spectrum The Hedgehog's alternate universe, Jack was also the Rookie, also formerly known as that timeline's Spectrum.

After being left behind in Metropolis during Operation Big Wave and then almost immediately being captured by Eggman and tortured for some time afterward, his trauma turned to insanity. After escaping Eggman, he would create an alter ego and utterly destroy the Eggman Empire, the Resistance, and the rest of the world with fear and death (causing its apocalypse, with him as its tyrannical ruler). Years later, he would be brought into Spectrum's main timeline, where he would fight against Spectrum himself for a time, but would then go off on his own into the multiverse and occasionally help either side of any future conflict.