Sorry, My Skills Are Automatically Maxed Out! - Ch. 13

[MangaDex]

 

[VooXoo]

I presume that the MC knowing the weak point of a super rare monster is because the author/studio got mombarded from comments about how they introduced him as a genius with top results at school but he was going around aimless like a idiot and didn't knew the weakpoint of monsters in dungeons for beginners.