ThunderCats - Season 4 - Eps 20: The Book of Omens
New Thundera is being torn apart and the Thundercats must present certain artifacts at various dangerous locations that used to be beautiful places, then Lion-O must go into the book and give the Key of Thundera to the guardian of the book ""at the 24th hour,"" or the Thundercats will be frozen in time and New Thundera will be destroyed. But Mumm-Ra steals the book and key and journeys into the book himself. He wants to save New Thundera BUT wants the Thundercats frozen in time. The Ancient Spirits of Evil try to stop Mumm-Ra because they fear if Mumm-Ra goes into the book, their powers will cease to exist. The other Thundercats run into problems also at the locations they are supposed to be at. Lion-O goes into the book using the Sword of Omens and battles Mumm-Ra one on one, neither of them using any magic. Even when Mumm-Ra cheats, Lion-O still wins. The ASOE summon their ""champion,"" Pyron, to then fight Lion-O, but Lion-O gets the dragons in the book to fry him... He presents the key
About ThunderCats

Title: ThunderCats
First Air Date: 1985-01-23
Last Air Date: 1989-09-29
Status: Ended
Rating: 8.247/10 (from 1044 votes)
Language: EN
Seasons: 5
Total Episodes: 130
Network: Syndication
Genres: Animation, Sci-Fi & Fantasy, Action & Adventure, Kids
Production Companies: Rankin/Bass Productions, Lorimar Telepictures
Synopsis
The inhabitants of the planet Thundera evacuate just before it is destroyed. They were pursued by a band of mutants. All but one of their escape ships was destroyed. Only a small group of Thunderans (Thundercats) remained. With only half engine power, the group, which was led by Jaga, had to set a course for the nearest planet. Jaga commanded their ship while the other seven were in their stasis tubes. Jaga died on their journey to Third Earth and their ship crashed there. Soon they made friends with various groups in the area and they designed a fortress. Mumm-Ra the centuries-old embodiment of evil, along with the mutants that destroyed the rest of the Thunderans are a constant threat. But Lion-O, the new leader of the Thundercats, with his weapon the "Sword of Omens" will help the Thundercats to have a standing chance.
Cast

Larry Kenney
Lion-O / Jackalman (voice)

Peter Newman
Tygra / WilyKat / Monkian (voice)

Earle Hyman
Panthro (voice)

Lynne Lipton
Cheetara / WilyKit (voice)

Earl Hammond
Mumm-Ra / Jaga / Vultureman (voice)

Bob McFadden
Snarf / Slithe (voice)

Gerrianne Raphael
Pumyra (voice)

Doug Preis
Alluro (voice)