I got a question dude how did the creator of scp 049 manage to create the hyper realistic images?

Never heard about him but sounds interesting.

But how do creators of scps manage to create those hyper realistic images

I think Doctor Manhattan might be the strongest villain, but I might be wrong.

I think that doctor Manhattan was not a villain but lost all emotions but he does care in a emotionless way .

I'd say the most powerful villain is Azathoth from the Cthulhu Mythos. Ageless, immortal and omnipotent. Created the universe by accident and should he ever wake up, the universe would cease to exist.