Apocalypse Redux - Book One

Decently written and interesting premise, but just plain boring.

Premise: MC starts off as the last remaining human, slaying high ranked monsters by the hundreds and he gets send back in time to try and save humanity.

Now instead of doing anything cool or interesting, he joins his local researcher group to gently speed up the process of humanity figuring out how the system works... and that's it. Neither the MC nor the side characters have any personality, there's no character development, the plot doesn't really move other than the first chapter, MC gets marginally ahead of the power curve, but doesn't want to stand out, so doesn't really do anything interesting... It's just boring.