AllSeeingBedroom

My original comment was about your Kamehameha obsession's anyways as I see it as a ray rather than a blue orb on that matter I won't question what stance you like balls delivered to you.

As I said many stances but its more reasonable than this. Like I know you have your opinions but make up your mind.

The color is the same with all the one with rasengun just have swirls of white but the stance is much different from Gokus spirit bomb as goku throws it like giving a double high five

That would be sick but considering that Ancient power is not really the cause of the lines evolution as shown in the game. Like most variant forms is more the effect of adapting to their environment like that of Alola forms but hisui is further fueled due the temporal energy release from mount coronet like the hisui starters in the games its hinted that it was due to the powers of Dialga, Palkia and Giratina. even arceus as shown in one of the movies that in the past the Alpha Pokemon himself used to visit the region in a regular basis leaving behind his plates. Their presence is strongly felt in the region in the past causing space time anomaly's to occur like in the games and even movie with Darkrai that when those legends interacts their power sends fluctuations in the Sinnoh region. I like the shelter reasoning though it could be used by the author as a pivot to explain how the mc can obtain a Hisuian Sliggoo in modern times just need to see whether or not the author consider adding a Goodra in the mc's team. Evolution with Ancient power is shown to Pokemon that doesn't need its final evolution due to the lack of danger like the pasts. They are not regional forms but of the same form just adapting their selves to not undergo further evolution as a bigger body means need for more food but able to be stronger in battles but the lack of danger made it so to be unnecessary. It would be funny to see several Pokemon using Ancient power as a ritual as a requirement for an evolution, imagine if it were in a game it would be in a battle and requires a double battle with both opponent attacking the Pokemon including its own team mate with Ancient power.

I hope so but the pokedex entry of Hisuian Sliggoo and even other Hisuian evolve forms makes it so its likely only possible in ancient Sinnoh where alot of space time shenanigans kept on happening in mount coronet causing Hisui to get the problems found in the legends. The author may force it in the story by catching a Goomy and force feeding it high concentration of iron to quote Hisuian Sliggoo's dex entry while also teaching it Shelter and make it so that it is the Goomy's evolution req to turn into Hisuian form