Speedster's Marathon

Rainbow Dash has been challnaged as the fastest in Equestia by another Storm King Family Member, called The Speed King, an annoyingly hyper-active yuts who even has his own over-used catchphrase "WA-ZAM?!" every time he shows up or does a stunt and is a VERY mocking asswipe! While another devient of the clan, he is however far from harmless and he demands Rainbow Dash to race against him, flight vs. his speed magic, and with the prize of a lost alicorn relic chalice he treats like a trophy, or if Rainbow loses, he becomes Speed King's bitch! Rainbow Dash was gonna refused, but the Speed King, not only mocked Rainbow as a chicken, but incrised the stakes by saying that if Rainbow doesn't race him, he'll run down to Tartarus and free all it's prisoners throughout Equestia! When Rainbow Dash is forced to race, Twilight fears that the Speed King won't race honorably, so the Lougers are asked to help look out for cheaters, and wouldn't you know it, Junjie and friends, Svengallop and Wind Rider, Dr. Callaberon and his goons, Aouizotal, and the Speed King's own henchmen, a slow-minded Grubber-like Sidekick called Slowpoke, are setting up traps to slow down Rainbow Dash. Can our heroes protect Equestia AND Rainbow Dash from a dirty cheat of a speedy wiseguy?