Sonic
Sonic the Hedgehog defines velocity as a core attribute of existence. His baseline running speed exceeds Mach 1 under casual conditions, representing his resting state rather than maximum exertion. Documentation across canonical game appearances confirms speeds approaching and occasionally exceeding light speed during periods of intense motivation.
The hedgehog's velocity extends to reaction time and cognitive processing. He perceives and responds to threats at supersonic rates, operating in temporal windows inaccessible to slower beings. In combat, this translates to near-instantaneous engagement capability against any opponent bound by conventional physics.
The Joker
The Joker possesses standard human physical capabilities, perhaps slightly below average given his slender frame and theatrical rather than athletic lifestyle. His movement speed approximates that of an untrained adult male, measured in single-digit miles per hour during running and substantially less during his characteristic theatrical swagger.
His reaction time operates within normal human parameters, relying on anticipation and preparation rather than genuine reflexive capability. Against opponents of superhuman speed, the Joker has historically relied upon pre-positioned traps and contingency plans rather than real-time response.