WilyKid

There isn't much known about Wilykid accept that he is the long, long, lost brother of the Thunderkittens. During the early years of Thundera, a set of triplets were born namely Wilykat, Kit, and Kid, during the birthing, one of the newborn kittens were stolen. He was taken to Third Earth, years before the arrival of the original ThunderCats. Wilykid was brought up on a deserted island. Among living on the island, he soon allied himself with the local ocean surfing natives. He fought off a band of seafaring pirates known as "The Sea Dogs".

During a sea battle with the Sea Dogs, Wilykid already an honorable member of the ocean surfers, decided to get help from the ThunderCats not realizing that he himself was a Thunderian. Traveled east to the mainland to Cats Lair which was being occupied by Lynx-O who had been made commander-in-chief of operations had assembled his band of ThunderCats to investigate the trouble. After nearly defeating the ThunderCats, Wilykid sent a message to King Lion-O. He sent a four-man team to do battle with the Sea Dogs, among the four-man team, was Wilykit who soon discovered that there was another ThunderKitten alive and well. Together they foiled the pirates and rescued Lynx-O's team. After getting back to New Thundera, Wilykid was reunited with his lost family. He liked being on his own, although the ThunderKittens wanted him to be inducted into the ThunderCats, he declined even though he was a Thunderian he liked living on Third Earth and not being told what to do. So they gained another ally in the forces of Good versus Evil.