@Mr X I believe its because its a mix of both the fact that gaming is known to train your reflexes to an expert degree, assuming you're pro, and the body he become, isn't lacking in any sort of way such as overweight or any broken limbs

@Izzy I may be wrong but i believe its due to the fact that human instinct priotizes survival, especially in situations such at this

@Moni I assume it's a mix of the distance from them, the only light being produced its from his abilities and the fact they don't know who he is, even if they catch a glimpse for a second. Though I may be wrong as it's just my understanding of it

@Ulric Holden  
I think he just wanted to see where he stands as a whole, strength, skill and experience. But instead what he saw was the monstrous strength that he possesses.
Correct me if I'm understanding it incorrectly

@Human

 
This probably gets answered in the next chapter, but he is a white piece and he took out the black piece, right as it became whites turn. And as it mentions, you don't need to follow the orders of the king, meaning that its actually the first piece to move that gets to, which in turn made it no longer whites turn, meaning the piece that was attempting to take the turn to move, touched the fog

Sorry for ranting on, but that basically covers the entire situation

@A lazy student who hates studying.  
You're all good, its just common place for people to forget a few things from prior chapters as they bulk read, so I try to be sure I cover things even if its meant to be a joke

@A lazy student who hates studying.  
I don't know if this is a joke or not, but remember his face is distorted both in reality and in memories for every being, no one can see his face due to his abilities

@Aeryan max Remember, he had to actually re-obtain his emotions in a sense to become a swordmaster