I Transmigrated into a Seated-In-Death Emperor Ancestor, Unbeatable and Invincible

[Decisive and ruthless + Invincible protagonist + No saintly do-gooder + One-shot kills + Bow to no one] Su Chen was inexplicably transported to a fantasy world, where he took over the body of the Su clan’s dying ancestor, whose lifespan had run out. The Great Qian Empire had twelve great imperial clans, with the Liu clan reigning supreme. Beyond the empire, in the Boundary Sea, the demon race watched like a tiger waiting to pounce. By command of Emperor Qian of the Liu clan, the founding emperor of the empire, the Su clan guarded the Boundary Sea and protected billions of lives. Now the current head of the Su clan had been gravely wounded suppressing the Demon Emperor. The clan’s other Great Emperors were all on their last legs. Su Chen had reached the end of his lifespan and was about to die, while the demons were on the verge of breaking through the boundary. Yet the Liu clan ordered the entire Su clan to return to the empire and stand trial! They accused the Su clan of using the demons as an excuse to swindle the resources the Liu clan had allocated over the past hundred thousand years. Just as the Su clan was about to be utterly destroyed, the System finally came online! [Host is on the verge of death. System successfully bound!] [Reward: Supreme Invincible VIP Gift Pack. Host’s cultivation increases by the cube every second, with no limit...] [Reward: Supreme Invincible Divine Technique, Desolate Sky-Prison Finger!] Su Chen: My cultivation increases by the cube? He was already at the peak of the Great Emperor realm, and his cultivation would grow every second, based on the previous second! Oh no, I can’t calculate it. My brain’s starting to itch! A quick calculation tells me I’m invincible! On this day, every living being in the Great Qian Empire clearly saw an enormous golden finger descend from the sky above the empire! Su Chen: This old man has spent a lifetime mastering countless techniques, but I’ll only need one move... Desolate Sky-Prison Finger!!