You Favored Your Younger Brother. Now That I've Become a Sword Immortal, What Do You Regret?

[System + Sword Immortal + supernatural abilities + invasion from another world + family regrets] Ning Cheng is the first person in the Ning family in nearly a century to awaken an S-rank ability. He was once the family's greatest hope, but that same year, his twin brother Ning Qi was found to possess a sword body and the potential to awaken as a Sword Immortal. Sword Immortals are among the strongest on the Dragon Kingdom's combat rankings, with far greater potential than Ning Cheng. So the family placed all its hopes in Ning Qi, and Ning Cheng became a nobody.

Unwilling to accept this, Ning Cheng wanted his parents to look at him again. He trained relentlessly, fought tooth and nail, and fought for territory, making the family stronger and returning to the higher-ups' attention.

But the family turned a blind eye to all this, instead believing it was all thanks to Ning Qi. They thought Ning Qi was the reason the higher-ups had noticed the Ning family again, completely ignoring Ning Cheng's efforts. In the end, when Ning Qi said that an S-rank ability user was needed as a sacrifice for him to perfectly awaken his Sword Immortal talent, the family members offered Ning Cheng up without hesitation. They then abandoned him outside the safety zone after he lost his abilities, leaving him to die.

By then, Ning Cheng was utterly disillusioned. He felt that everything he had pursued in life was a joke. He had given everything for his family, but they had treated him as a disposable pawn. He could only regret that he had realized the truth too late, leaving him no chance for revenge. Just as he thought this, a chime rang, and a voice sounded in his heart: "Host, you have been detected to possess the talent of a Great Sword Immortal. Would you like to awaken it?" Ning Cheng awakened it without hesitation, then rose to power and grew stronger and stronger, becoming a pillar of strength for humanity. Later, the Ning family looked at Ning Cheng, now beyond their reach, and regretted everything. But it was too late...