The Time Skeletons are a group of three people, that Marjo is the leader, while Grocky is the brains and Walther is the muscle, which they were the first villain trio in Tatsunoko.
Marjo is voiced by Stephanie Sheh in the English dub and her Japanese voice is unknown, due to the loss of Noriko Ohara.
Grocky is voiced by Charlie Adler in the English dub and he is voiced by Daiki Yamashita in the Japanese dub as a tribute for Joij Yanami.
Walther is voiced by Kevin Michael Richardson in the English dub, and he is now voiced by Masashi Ebara in the Japanese dub, as a tribute for Kazuya Tatekabe.