Lore from the games is used to make this movie but the story is still generic. Evil guy trying to capture strong pokemon and Ash stops him. A little bit of backstory is given to the evil guy and there is only one side character, who is also related to the evil guy, which is excellent and makes the story better than most of the generic evil guy pokemon movies. And also evil guys were missing for a long time in pokemon movies so coming back to old strategies is not that bad.
Art and sound have always been great in pokemon movies.
A major problem is Shaymin's character. It is too bratty and annoying. I guess they made Shaymin like this because Manaphy wasn't that different from Mew, Jirachi, and Celebi. So, at least Shaymin is unique.
Action scenes were not as strong as Deoxys vs Rayquaza but the choreography is good enough to make them memorable. And the scene where Regigigas enters with Mamoswines was cool.
