Life after light

A manga
The general conducts unspeakable experiments: injecting the living with the Tall One virus, twisting their bodies into new abominations-hulking, armored beasts fused with metal and bone, obedient only to him. Innocent civilians are dragged from their hiding places, slaughtered in droves, then resurrected as shambling slaves. Their minds are burned away, leaving only hollow-eyed puppets who march in perfect formation, whispering their master's name even as they devour their own families. In the final days of civilization, a ragged platoon of soldiers discovers the horrifying truth: the world is already dead. Stranded on a fog-choked island, they turn the last safe harbor into a quarantine zone-herding terrified survivors behind razor wire and concrete walls. But safety is an illusion.

And then the real war begins.
A rogue general-once the most decorated commander alive-has claimed the island as his personal kingdom. With the most elite fighting force left on Earth at his command, he launches a merciless siege. His goal is total dominion, and he will pay any price in human flesh to achieve it.