Pic slightly related but is all over the place

According to the Riddler, Ghetsis is the true villain of US/UM. Also according to one theory, there is a fourth member of the creation trio...

Dialga is solid (steel), Palkia is liquid (water), Giratina is gas (ghost) and the original dragon would be plasma (like team plasma, it would be fire and electric Type or maybe pure dragon)

Both fire and electricity give off plasma so the original Dragon would be the true plasma Pokemon and plasma has a lot to do with light.

Also I don't think the picture everyone is calling "Necrozmas true form" is really it's true form because Necrozma is really a light absorbing monster so a being of light would technically be its rival.

Finally Zygarde the order and balance Pokemon is there for a reason... Maybe it's not the Ultra Beasts since they seem to be handled pretty well by the Tapu Guardians, and Necrozma seems to be handled by the player and the Legendaries. Maybe there is something bigger out there

(Sorry for formatting)