Mordecai, retaining his aloof, slightly cynical personality but with a heightened sense of speed and agility, would be a blue, anthropomorphic bird, possibly a robin or jay, with quills sprouting from his head. His attire would be a modernized take on his usual attire, perhaps a sleeveless, sporty jacket over a fitted shirt, and shoes designed for running. He might possess a special ability related to flight, such as super-speed flight or the ability to create powerful gusts of wind. His overall design would lean towards a more streamlined, athletic build, reflecting his newfound Mobian speed.

Rigby, on the other hand, would undergo a more drastic transformation. As a raccoon, he would be significantly smaller and more agile than Mordecai, embodying a mischievous and energetic personality. His fur would be a darker shade, perhaps a charcoal grey or black, with lighter accents. He might have a more pronounced snout and sharper teeth, reflecting his often-impish nature. His attire would be more casual, perhaps a pair of shorts and a t-shirt, but with added elements like gloves or wristbands to enhance his abilities. His special ability could be related to his innate cunning and dexterity, perhaps enhanced senses, the ability to climb and scale surfaces with incredible speed, or even the power to create small gadgets and tools from scrap.

Their dynamic would remain largely the same, with Mordecai acting as the more level-headed and responsible one, while Rigby provides the impulsive energy and often comedic relief. However, their Mobian forms would allow for more dynamic action sequences and a wider range of scenarios, potentially involving high-speed chases, platforming challenges, and battles against unique Mobian-style antagonists. The park setting could be reimagined as a vibrant, sprawling zone within the Mobius world, complete with its own unique challenges and inhabitants. Their interactions with other Mobian characters could be explored, potentially leading to humorous and unexpected encounters. The overall aesthetic would be a blend of the familiar Regular Show humor and the fast-paced action and vibrant world of the Sonic the Hedgehog universe.