Webnovel Author: Revonne - Novel Collection

It's rebirth, not rebirth into the past. It's like dying and then being reborn a few years later. One can't know the future in that case.

That's the thing. He's not saying it after working extremely hard and becoming stronger, he's saying it before that when all he sees is death around him. It's like if someone (Who has a good and peaceful life on earth) is suddenly tossed in hell. his first thought would be, if there's a way to return to the safe peaceful life that he had, instead of dying there. His first thought won't be, how can I survive all death flags here to make this my home. That thought can only come after becoming stronger.

Eren

Yes, but only if he attacks with it.

Currently, the Empire is weaker than the Continents. First, their population is lower. And the second and most important reason has to do with an important part of the story to come. Can't go into too much detail without spoilers.

That is correct. Mana is mostly related to Necromancer Tower's continent, but people from other continents can also have mana without realising. It will most probably be explored more in the future.

Eren is his real name, which he had on earth. Ren or Elder Ren is what the people of this world know him as, because it's the character's name. So when it's from the Character's perspective, it is mentioned as Ren.

Eren is his real world name, Ren is his novel name.