The Abyssal Ruins is a mysterious pyramid structure on the bottom of the seafloor near Undella Beach.
It is filled with ancient artifacts and ancient scriptures on the walls. To properly navigate the ruins,
one must turn at every intersection that is a prime number(so turn at the 2,3,5,7,11th intersection) on each of the three floors.

The scriptures, when translated and deciphered, report mainly about a king, who was virtuous, kind and strong.
The scriptures on the third floor of the structure tell about some historical events, depicting particular entities with individual symbols,
in stead of a 1 to 1 translation and cipher, like the other words.

Symbol 2 refers to the enemy of the civilisation of the ruins. It depicts a humanoid creature, that is most likely a human. "human"(5) fits with the translation.
However, if human was the enemy of the civilisation and the king defeated him, can the king be human?
I believe the king is, in fact, not human, but a pokemon.

Symbol 3 is swapped with symbol 2 between B(2) and W(2). Therefore, I believe that they are refering to the same entity, yet with a differen meaning.
I think symbol 3 stands for "chaos"(5), "enemy"(5) or "discord"(7).
The symbol vaguely seems to resemble "unown"(5), but in that case the 2 symbols can't refer to the same, which I think to be highly unlikely.

Symbol 1 is referring to the "king". But who was the king?
We know that the king:
-has the capability to "Shine bright", e.g. with a move like Flash
-has the capability to "show strength" e.g. with a move like Strength
-can be both powerful and kind
-has a name consisting of 8 letters

The list of pokemon with 8 letters knowing Flash and Strength reveals an interesting possibility: