C140 Tomb

Why did the Lebronto-seijin wantonly spread its own genetic material in the universe?

Why did the individuals who possessed the genetic material of the Lebronto-seijin kill each other until the very last person?

Also, why did Zetton-seijin, who had given up on the power of the Leonix, suddenly change his mind and choose to escape from his younger brother's hands?

"If that's the truth..