Sam, a snake who recently transmigrated with a system, faces immediate danger when his parents present his tiny beast core to Lord Redfang. They call him useless; Sam insists he'll die without it. Lord Redfang scorns the core, accepts a Bloodspirit Fruit, and orders a hunt in three days to collect wolf beast cores. Sam's system detects critical life signs, activates automatic devour, consuming bones and rotten flesh and gaining one evolution point. He switches to manual mode, devours common bones, and his beast core begins repairing. He has three days to recover before the hunt.
Redfang's forces assault Blackwind Cliff to annihilate the Wolf Clan and seize wolf beast cores. As bodies pile up, a Serpent Clan member secretly devours wolf corpses, restoring his beast core and earning evolution points—his tally jumps to 59. Mid-cleanup he panics at being exposed, admits "I'm a snake," and carries out orders to collect beast cores and dump scraps. Counting his new power and nursing old grievances against Redfang and his parents, he decides to plan revenge and vows to devour every last one of them.
Followers hail him a prodigy and schedule a clan assembly in three days; the host spends 1,000 evolution points to evolve. He becomes a Shadow Obsidian Spirit Serpent, gaining Conceal Presence and Venom Fang Pierce. He plans to lie low and later settle the score with the Serpent Clan, even considering devouring Redfang for points. While hiding he devours an adult bear demon and gains 150 points, bringing his total to 295. With new skills but only 295 points and the assembly looming, he must choose: stay hidden or hunt Redfang to reach the power needed to confront the clan.
At a Serpent Clan assembly Hydro Dragon envoys arrive to assess Lord Redfang, a Transformation-stage prodigy. They issue a challenge: within three days Redfang must defeat the Obsidian Turtle at Blackwind Cliff, retrieve its beast core, and present it to the Hydro Dragon outpost to win promotion to two-star. Redfang immediately selects fifty elite warriors and marches into Blackwind Cliff. Other clans note that promotion brings tribute and eye quick gains, with the Wolf Clan already overdue. Redfang's three-day hunt for the core begins, and the clan's promotion hangs on his success.
A group sets up the Serpent Scale Formation to seize the Obsidian Turtle's beast core. Redfang attacks but the turtle retaliates, emitting a freezing venom mist that nearly collapses the Formation. Wounded and outmatched, Redfang retreats, vowing to return in three days stronger to take the core. A hidden onlooker notes both sides are crippled—Redfang fled and the turtle defenseless—and declares devouring the turtle would propel them to the next level. The episode ends as that predator moves in to consume the crippled turtle before Redfang's promised comeback.
When attackers ambush a weakened snake with poison, the reptile panics but survives after the ally Redfang tears a hole in an Obsidian Turtle's shell. The snake devours the turtle's meat, limbs, shell and core, gaining evolution points and triggering a second evolution. Faced with Frostborn Breath or Obsidian Shell, the host rejects frost—Conceal Presence and Venom Fang favor ambush—choosing Obsidian Shell. He evolves into an Armored Serpent with greatly boosted defense. He then vows, "it's time for you to pay the price for what you took," and prepares to confront his parents.
A gravely injured clan lord poisoned by the Obsidian Turtle is urged by an attendant to drink a century-old bloodroot cure and absorb a beast core to purge the venom. While he recovers, an assassin from the same clan ambushes him, wielding fire and accusing him of devouring a Wolf Clan beast core. The attack accelerates the venom when the lord struggles, but the accused suddenly evolves—transforming into a Serpent, gaining thousands of evolution points as he devours a remnant Wolf Clan core. The sudden evolution stops the assassin in his tracks; third evolution begins, leaving the outcome unresolved.
After consuming Redfang the host-serpent immediately levels up—Invisibility and Savage Deathfang replace older skills—and confronts his clan. A parent and other serpents beg for mercy and claim they were forced, but he rejects excuses and begins devouring them to collect evolution points. Feeding on hundreds of serpents pushes his points past 15,000 and triggers a fourth evolution. He becomes an Infernal Acrid Serpent and acquires Viper Miasma and Soul Drain. Triumphant, he announces Redfang and two Hydro Dragon clan members as his next targets and sets a three-day deadline to feast, leaving their fate unresolved.
Hydro Dragon envoys demand the Obsidian Turtle beast core after three days. They find a poison trace that isn’t the Obsidian Turtle's freezing venom and assume Redfang is dead. While they flaunt their armor, miasma appears and corrodes spiritual power. A hidden Serpent Clan fighter strikes from the shadows and the envoys are overwhelmed. The attacker devours both Hydro Dragons, gaining thousands of evolution points until a system detects enough pure spiritual power to unlock the fifth evolution. The episode ends as Transformation is initiated, leaving the Serpent attacker poised to reveal its new power.
Transmigrated as an abandoned offspring of a snake clan, Sam Cole is betrayed before birth when his parents attempt to sacrifice him for his beast core. Barely bound to a Devouring System, he learns to gnaw bones, consume demon beasts and absorb spiritual veins. The hunger transforms him into the Infernal Ancestral Dragon. He erupts in revenge, crushing those who hunted him and unifying the fractured Demon Realm. Refusing to bow to world-devouring laws, he crosses dimensions to slay the demon ancestor itself. Victorious, he forges trade between human and demon realms and imposes a new order across worlds. Yet even as power crowns him, ancient crises stir beyond this realm. The useless snake has risen, but more terrifying existences now watch from the dark.