Crocs_is_Dead
It would have been better, in my opinion, if you stayed with the original idea of SL with a unique dungeon related to the mc explaining why he can level up quickly now. I mean, if the suspicion before entering the gate were a call because it was a dungeon for him, it would explain why he couldn't get stronger in 6years, and now swinging his sword or playing with his knife can give him power. (A possible reason would be because there is void energy inside this portal that wasn't present on earth due to its recent awakening)