Arknights: The Forgotten King

Camelot, the kingdom that was once ruled by King Arthur Pendragon. A beautiful city filled with culture and brimming with wonders and mysteries, but. in the end it fell like the rest of the old kingdom's not even a trace of the once beautiful city, all of their hard work gone, Forgotten or haven't been found. Its history from the rise and the fall of Camelot is recorded in history books or simple bedtime stories.

But what if, this wasn't the first time that the kingdom of Camelot fell. But What if it was the second forgotten history of Camelot, the forgotten king, the first Pendragon, and the creator of the first table of the round.

Who is he? What happened to him? And where is currently?
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" I won't be remembered by the good or the bad deeds I've done, it is better for me to be forgotten about rather being remembered. "

Ps: I rewrote this I wasn't happy with the previous one.