Many people recommended this manhwa but i never picked it up before since i didnt really like the art style, and i can travel back in time, i'll slap my past self for reading through 400 chapters of it just because some random guy said it gets better. Sure, it does get better, but its only better because the first season is just so horrible that it makes even mediocre seasons after it become somewhat better. Even among manhwas, its far from being one of the best, there are a lot of better manhwas than it, even the isekai/resurrection manhwas with around 20-30 chapters have more plot than it.

Story 3/10: the author had a good start with our protagonist being mysterious and all to get people to keep reading to find out his past, but from there on, it just keeps going downhill, i've read 400 chapters and still dont know anything noteworthy, the storytelling is poor, the author tries to tell us the stories of so many characters and trials/trainings at a time, and surprisingly none of them is interesting, and then the main plot never gets anywhere because all of these side stories keep overwhelm it.

Art 7/10: the art at the start is also horrible, the characters look like theyre made on MS paint, but it does get better after some 100 chapters or so, and its also the only thing that rly gets better in this manhwa, although the character poses are still stiff even after 400 chapters.

Characters 3/10: the worst part of this manhwa, the main character of the story is mysterious, and he remain so even after 4 seasons, we dont know anything about him aside from a few things from his past, he started off as the "i will get stronger to protect all my friends" protagonist just like in shounen manga, but he never gets anything more than that, he rarely shows emotions and rarely says anything. The main antagonist is even worse, for a bad guy, the main antagonist of the series have the worst reason ever to become a bad guy, and just like the protagonist, we rarely know anything about her except for her being mediocre. All characters other than the main guy and the main bad guy are basically there to be part of the crowd, even though the author tells a lot of side stories about these characters, we never even get a chance to get attached to them, because when the author is done telling their stories, they're thrown away to make room for new side characters, this thing happened every season.

Enjoyment 3/10: i read this because i ran out of manga to read and thought that it was a good time to start reading this, and that was the worst decision of my life, i forced my way through 400 chapters of this manhwa and barely gets any enjoyment, everytime something promising happens, the author just start to ruin it like the way he did in the last season, by introducing "new" characters, telling "new" stories, that somehow just end up like the last season, everything leads to a big battle at the end and protagonist end up having to leave his friends behind to find a way to get stronger and somehow gets new friends in the process.

Overall 4/10: main plot is barely developed even after 400 chapters, all the side plot are not intersting and the author just keep going in this pattern, art is somewhat bearable, characters are just bland and shallow even when a lot of the plot focus on their stories in stead of the main characters.
I know that everyone have different tastes, but for me this manhwa is even less interesting than some isekai/ressurection manga/manhwa/manhua by some nameless authors that only have about 20 chapters overall, even those kind of stories have more plot than this.
Dont let anyone trick you into reading this manhwa saying that it gets better, it actually doesnt.