Reincarnated as Parasitic Tentacle - Chapter 80: End of War

I exist in the darkness, disappear under the bright light, and will eventually devour the sun and turn into the shadow of all things… Known by people as the indescribable terror of darkness; the king of shadows; the dark day; the existence of the shadow of the world , is still just a somewhat special high school student, facing a weird death game…

- Description from novelbuddy

Reidar's seemingly ordinary trip to visit his parents spirals into a chilling nightmare as reality itself begins to unravel. After losing consciousness, he awakens to a horrifying revelation: he is not alone. Monsters lurk in the shadows, and the world he once knew has transformed into a realm of terror.But the strangeness doesn't end there. An alien force has implanted a mysterious system within his mind, granting him access to unimaginable power and knowledge. Through this newfound connection, Reidar discovers that the world has met its catastrophic end—the apocalypse has arrived, and with it, he has acquired extraordinary powers that defy comprehension.Join Reidar on his thrilling quest for dominance as he harnesses his abilities to amass an unstoppable army of beasts, valiant knights, and relentless undead. Follow his rise to power as he becomes a force of nature, feared by all, including those who gave him the very powers he now wields.

Follow Chen Ming as he accepts disciples, establishes a sect, and fights his way in a world that deems him a cannon fodder.
He goes against any common sense using his wits and novel knowhow to finish missions and arm himself against his cruel fate.

- Description from Novelupdates

On this land of real souls, with millions of different martial art institutions, there’re so many strong fighters just like the trees in the forests.