Inuyasha the Movie: Fire on the Mystic Island is the fourth and final Inuyasha film, released in 2004.
The action takes place on Horai Island, a mysterious island that only appears once every fifty years where humans and youkai live together in harmony. Unfortunately, said harmony is ruined by the tyranny of the Four War Gods, who take over and torment the populace. One resident, a half-demon child named Ai, manages to escape the island and track down none other than Inuyasha and his companions for help.
Beware of unmarked spoilers!
Inuyasha the Movie: Fire on the Mystic Island contains examples of the following tropes:
- Art Shift: Averted. Unlike the other three films, Fire on the Mystic Island features the same character designer as the anime series.
- Adaptation Expansion: Episodes 146 and 147 of the anime stated that Inuyasha and Kikyo visited a mysterious island that only appears once every 50 years. This film reveals that they actually visited Horai Island.
- Ambiguously Human: Kikyo's clone has fangs.
- Blood Magic: Ryura, one of the War Gods, created a clone of Kikyo by taking a sample of her blood.
- Chekhov's Gun: The bow and arrow Kikyo leaves behind is used by Kagome in the finale to help Inuyasha defeat the Four War Gods' final form. Its' possibly subverted; all Kagome's arrow has time to do is hit the aforementioned Four War Gods' barrier before Inuyasha's own attack hits and blows them away.
- Cloning Blues: The War Gods create a clone of Kikyo to use as a slave.
- Contrived Coincidence: Inuyasha, Sesshomaru, and Kikyo were all attacked and marked by the War Gods in the past, and all three arrive on Horai Island after it resurfaces.
- Deadly Hug: When Inuyasha can't bring himself to kill the Kikyo clone, she embraces him and seems poised to bite into his neck before the real Kikyo shows up and takes her down.
- Dual Wielding: Ryura, the leader of the Four War Gods, fights with two swords.
- Forgotten Phlebotinum: The Final Boss is defeated by Inuyasha combining the Tessaiga's Backlash Wave with the Adamant Barrage. A combination that is never seen again.
- This is made more apparent in the original Japanese version of the movie. Inuyasha even goes as far as to call his final attack the 'Adamant Backlash Wave'. Why the attack is only referred to as the Backlash Wave in the dubbed version is unknown.
- The Four Gods: The villains are based off of The Four Gods.
- Grand Finale: Could be considered this to the original Inuyasha anime in a way, as the film was released a few months after the anime's final episode.
- Half-Breed Discrimination: Averted; on Horai Island, humans and youkai live in peace and even produce hanyo children who are treated just like everyone else.
- "I Know You're in There Somewhere" Fight: Inuyasha tries this on Kikyo's clone at first, but gives up when he discovers it's not the real deal.
- Lightning Bruiser: Unlike the real Kikyo, the Kikyo clone is a Master Swordswoman who is able to physically fight Inuyasha one-on-one.
- No-Sell: Being marked by the Four War Gods seems to have no noticeable effect on Sesshomaru, as he can still leave Horai Island at will.
- One-Winged Angel: Jura goes this after losing his Thunder Cannon.
- Powered by a Forsaken Child: The Half-Demon children of Horai Island are sacrificed to the Caulron of Resonance to give the Four War Gods extra power.
- Shapeshifter Guilt Trip: Inuyasha manages to overpower the Kikyo clone, but he can't bring himself to kill her; the real Kikyo proceeds to show up and kill the clone herself before berating Inuyasha for letting himself be tricked by the fake.
- Shout-Out: Moegi has green hair and small horns on her head. Does that sound familiar?
- Also Ryura, Kyora, and Jura all bear resemblances to Herb, Saffron, and Lime of Ranma 1/2.
- Turtle Power: Gora is a humongous turtle in contrast to his humanoid brothers and has the power to sink islands.
- You Can't Go Home Again: The film ends with the destruction of Horai Island and the six half-demon children who escaped leaving to find their place in the world.