Pokémon: Arceus and the Jewel of Life
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This is the 12th movie based on the Pokémon TV series. It also concludes a trilogy which began with the 10th movie and continued in the 11th movie.
Ash, Brock, and Dawn arrive in a place called Michina. Ash and Dawn have a tag battle against some random people they meet, who later tell them about some local ruins. So our heroes go to check that out, but they run into some kind of weird atmospheric disturbance. They're rescued by a pair of guardians of the ruins, named Sheena and Kevin. Sheena has the ability to sync her heart with the hearts of pokemon, and she calls forth Dialga to help out. But Giratina shows up and battles Dialga. Sheena can't communicate with Giratina at first, because it has too much rage, but Ash manages to calm it down, since they'd met in the previous movie. After that, Sheena manages to get Giratina and Dialga to go back to their respective dimensions.
Then Sheena and Kevin take the kids into the ruins, which are of a shrine to a deity pokemon called Arceus, which had, according to legend, created its own world, along with those of Palkia, Dialga, and Giratina. Sheena explains that Arceus has been sleeping a long time, and energy is starting to surround it, as it's about to awaken. This apparently brought Dialga and Palkia's worlds into contact, which caused the battle from the 10th movie, I guess. We also learn that long ago, Arceus had risked its life to protect Michina from meteors. But the land was left barren, so Arceus gave up several of its defensive powers to create the Jewel of Life, which it entrusted to a man named Damos (Sheena's ancestor, who had the same power she does), to rejuvenate the land. Damos was supposed to return the Jewel later, but he betrayed Arceus, refusing to return the Jewel. There was a great battle in which Arceus destroyed the shrine, and then it returned to its dimension to sleep, and heal its wounds.
For generations, Damos's descendants have guarded the Jewel of Life, awaiting Arceus's return so they could give the Jewel back to its rightful owner. However, when Arceus returns, it destroys the Jewel, which was a fake. This greatly surprised Sheena, but Arceus believed she had attempted to deceive it, as Damos had. So it attacks the ruins, wanting to bring the humans to justice. However, Palkia and Dialga show up to defend the humans, and then Giratina shows up to help, as well. Dialga sends Ash, Brock, Dawn, and Sheena back in time, to the day Damos had betrayed Arceus. During the battle that originally destroyed the shrine, Dialga sends them back even futher in time. Sheena talks to Marcus (apparently the local ruler), while the others are sent to a dungeon, where they meet Damos. They learn that Damos had no intention of betraying Arceus, Marcus was actually behind that.
Well, Marcus tricks Sheena, but our heroes eventually manage to change the past, returning the Jewel to Arceus, though not until after a terrible battle, in which Marcus nearly killed Arceus, and the time travelers were nearly erased from existence (or at least from the past). But, as always, the good guys win in the end, and return to their own time. It kind of bugged me how it ended when they returned, because I had already been writing an end in my head. I'm a fan of time travel stories, of course, so I know how these things are supposed to work. But it didn't happen as it should have. But... time did correct itself, it just took a little while. (I should have known how it would happen, it was just the way things always happen in Pokemon stories. Anyway, it's not like anyone watches Pokemon for hard SF.) Aside from this one quibble, I thought it was a good movie, definitely the best of the trilogy, and I think in retrospect it makes me appreciate the first two movies more than I did before.