Taoola, Charcunga, and the third planet in alignment
The Unnamed Third Planet is an unidentified planet located in close proximity to Taoola and Charcunga.
Every thousand years, all three planets align in a way which allows Mortos der Soulstealer to escape from "the place beneath the Overworld" and walk the Earth for a single day. Other than that, nothing about any of the planets is known, not even which is which.
All three planets make their only appearance in the "Mortos der Soulstealer" episode.