[No heroine + happy ending that makes up for past regrets + overpowered protagonist]
Chen Shen is reborn in the world of Naruto, taking over Nagato's body. At death's door, he awakens a Trait Plundering System and a portal to the world of Fairy Tail.
In the Naruto world, he battles the Legendary Sannin and plunders Tsunade's traits, "Creation Rebirth" and "Strength of a Hundred Seal"; Jiraiya's "Sage Mode"; and Orochimaru's "Cursed Seal Power" and "Impure World Reincarnation."
He plunders the traits of every member of the Akatsuki: Itachi's "Susanoo," "Amaterasu," and "Tsukuyomi"; Deidara's "C0: Self-Destruction"; Sasori's "Puppet Performance: Hundred Puppets," and more.
He captures the Tailed Beasts and plunders all their traits, awakening the power of the Six Paths. I am the Ten-Tails!
He arrives at the Five Kage Summit and plunders the Kage's traits, including "Dust Release," "Lightning Release," and "Lava Release."
He transmigrates to the world of Fairy Tail, takes on the Thunder Legion, and plunders the traits "Lightning Dragon Slayer Magic," "Petrifying Eye," and "Eye of Molding."
He challenges all the S-Class Mages and plunders Mirajane's "Take Over Magic: Satan Soul," Gildarts's "Crash Magic," Erza's "Knight," and Mystogan's "Heavenly Body Magic."
He defeats the Spriggan 12, gathers every Dragon Slayer Magic and God Slayer Magic on the continent, kills the Black Dragon in an instant, and even takes on the gods single-handedly.
Itachi: He can turn targets to stone? What a bizarre ocular jutsu!
Sasuke: He actually ate my Fire Style: Fireball Jutsu and Kirin?!
Naruto: He can eat the Rasenshuriken too?!
Zeref: His magic is the true black magic that controls life and death!
Mavis: He lifted a god's curse by killing the god?
Talk no Jutsu? Yeah, right. Your grandpa Nagato believes only in world peace!
Yes, although the progress is a little faster, the writing is good. I look forward to adding new worlds in the future. By the way, who is the heroine? Still many girls.
If you men don't want to settle down, you will be considered to be romantic. If we women don't want to settle down, we will be considered to have been emotionally hurt.