MTL - Rubik’s Cube Heavens - v6 Chapter 77 convention

Ling Xiao was a powerful martial expert who fell in battle and was unexpectedly transmigrated into another world. He began life anew in the body of a boy with the same name, a fallen genius of the Ling Family whose cultivation had been crippled in a surprise attack, and son to a father who had also suspiciously been crippled under similar circumstances. Armed with knowledge from his previous life, Ling Xiao aim to restore his strength and establish his place at the top of this new world

- Description from Novelupdates

"God of Mischief is interested in you and wants you to be his emissary. Do you accept?"

With blood and wounds covered his entire body, the voice echoing inside his mind was like that of a hope shining upon him.

In the glorious future era, mankind had discovered the bottom of the sea and conquered the sky, but they also accidentally opened the Pandora box that shouldn't be opened. They found a place where lived numerous unknown creatures.

Here, humans will wrest their lives to step upon their greatest evolution and create their own myths, including Theodore.

Faced with betrayals, surrounded by beasts, and faced with imminent death, he answered with resolve and tenacity.

"Yes!"

This story is set during the end of the Sui Dynasty, a time where multiple powers struggled for supremacy and power.

Into the fray enters two orphans Kou Zhong and Xu Ziling; these two youths by many chances and luck obtain ‘The Secret to Long Life’ allowing the two to obtain profound martial abilities and a chance to rise to the top in this age of turmoil.

In a world teeming with Titans, Colossals, Gigantic Monsters and Kaiju's, Erian who reincarnated makes his living collecting scraps of low-grade Defective Genetic Serum, realised he transmigrated along with his system.

Follow Erian as he grows to become the strongest Disaster Grade Titan with the help of his Titan System!