Sparks Nevada killed Kevin's parents while saving Croach the Tracker from giant spiders at the Caves of Zzyzzx in the episode Spiders, Man. Kevin then gains the ability to talk when all animals are able to because of an Animal Talking Technology device activated by Technos the Advanced.
Kevin's plan to trap Sparks Nevada in a giant web is quickly foiled when Sparks' horse, Mercury, is easily able to get out of the web using his pistons. Kevin later shows up while Sparks is confronting Technos the Advanced. When Technos sics her Technologobots on Kevin, Sparks Nevada saves his life, forcing Kevin to re-think his Blood Oath.
Kevin got engaged to Jindlefer Lynchtree and was on his way to see his extended giant spider family when Sparks killed them. Kevin captured Sparks and Croach intending on taking vengeance when Raythum Lynchtree shows up intending to stop the wedding and kill Kevin. Sparks ends up saving Kevin, causing Kevin to face another puzzler. Kevin leaves hoping never to cross paths with Nevada again.