The Emperor has returned! Fuelled by rage and dark magic, he sets to work reclaiming the Eastern Caverns with new superweapons at his side: the Unstoppable Warriors. True to their name, the huge Warriors seem impossible to beat. As the Shane Gang race across the Eastern Caverns in search of a way to defeat them, they come up against hordes of Underlords and the fury of the Dai-Fu. Junjie's ancestors thwarted the Emperor's schemes for centuries, but they never faced a threat like this. Now all hope lies with the Shane Gang to defeat the Emperor once and for all.
Junjie recounts the ancient history of the Eastern Caverns and his ancestors, and the events that led to his downfall and transformation from the Eastern Champion to the Dark Slinger.
When Pronto accidentally uses the Emperor's sword blaster, he can suddenly do no wrong. Meanwhile, Lady Dai-Fu manipulates Underlord Holt into trapping the Shane Gang with a new superweapon: the Iron Warrior!
The Emperor sets to work creating Unstoppable Warriors to reclaim the Eastern Caverns. To make things even more difficult, a bounty is placed on Junjie's head, sending the Dai-Fu and hordes of the Emperor's Underlords after the Shane Gang.
Junjie, Eli and the Gang rally their friends in the Eastern Caverns—and even some of their old enemies—to help them take down the Emperor and all of his Unstoppable Warriors once and for all!
- Sam Vincent - Eli Shane, Yarry
- Lee Tockar - Pronto, Holt, Jonny Man, Sleade
- Shannon Chan-Kent - Trixie, Hoshi
- Andrew Francis - Kord
- Vincent Tong - Junjie, Symothy, Yang
- Brian Drummond - The Emperor, Hamengku, Shadow Clan
- Kathleen Barr - Lian/Dai-Fu, Drucilla
- Andrew Duncan - Swick
- Michael Dobson - Morv, Oogleby
- Mark Oliver - Pyritor
- "Slugterra: The Emperor's Revenge" in chronological order is the fifth film in the series and is comprised of "The Fall of the Eastern Champion", "The Lady and the Sword", "The Emperor Strikes Back" and "The Return of the Eastern Champion"; the last four episodes in Season Three.
- Although the episodes have already aired numerous times, the film itself premieres on September 27, 2016.
Opening Theme Song
The Slugterra: The Emperor's Revenge has a new opening theme song for the movie. The new opening is similar to the one in "Slugterra: Eastern Caverns", which is also around 1 minute and 24 seconds long.
- Junjie is added into both openings as part of the Shane Gang.
- The names of the people who work in the movie are shown in both openings.
- The beginning of both opening theme song show the Shane Gang and their favourite slugs on their shoulders, standing in front of the opening garage door in the Shane Hideout.
- After the title of the movies are shown, the Shane Gang is seen walking out of the garage in slow motion.
- Both openings show the Mecha Beasts being activated, showing that the Shane Gang are ready for action.
- Both openings show the scene when Eli wears his gloves, taken from "The World Beneath Our Feet Part 1".
- Both openings have the faces of the five members of the Shane Gang shown in close ups when the theme song begins to play.
- The word "Slugterra" is only yelled once instead of three in both openings.
- The title of the movie is shown with a black and red background, not black and blue.
- Instead showing the Shane Gang's blasters and slugs, this opening shows The Emperor, who has been turned to stone in the end of "Slugterra: Eastern Caverns" in different angles and accompanied with a black and red background.
- This opening shows three ghouls, in which two are a Flatulo Rex and a Ghoul Blastipede, in a ghoul rack close up, accompanied with a black and red background.
- The Emperor's Sword Blaster is also shown.
- The music in this opening is eerie and dark, as opposed to the energetic and lively music used in the original openings and the opening in "Slugterra: Eastern Caverns".