Episode 7 of Solo Leveling kicks off with a gentleman presenting Woo with a stack of documents detailing Sung and Yoo's recent dungeon expedition alongside Hwang and their companions. Despite the man's evident apprehension regarding the mission, Woo remains indifferent, showing little interest in delving into the matter himself. To pique Woo's curiosity, the man unfolds further intricacies about the expedition's participants.
Sung arrives home, laden with a feast of chickens and other mouthwatering delicacies. Jinah greets him warmly, and Sung shares the good news that he'll soon be able to cover their hospital bills and other essential expenses. As they savor their meal, Jinah inquires about Sung's recent dungeon escapade, peppering him with questions about his well-being and his fellow party members.
Reflecting on his experiences, Sung senses a transformation within himself. Jinah notices a shift in Sung's demeanor and asks if he's alright. Sung reassures her with a nod, but internally, he's laser-focused on growing stronger and surviving at all costs. He silently vows that if faced with a similar dilemma again, he wouldn't hesitate to eliminate more humans. Suddenly, the Player Log system alerts him that the beverage he's consuming is potentially harmful.
Undeterred, Sung retreats to his room and continues sipping his alcohol. He's puzzled when he fails to feel the intoxicating effects and wonders if the Player Log system is intervening. The system then informs Sung that a reward from his double dungeon feat is shielding him from the beverage's detrimental effects. Realization dawns on him; this is the reason his limbs regenerated after that catastrophic incident.
Later, Jinah gently wakes Sung and informs him that Yoo wishes to meet him at a cafe. At the cafe, Yoo unveils his plan to form a Strike Team and enthusiastically invites Sung to join him on approximately nineteen dungeon expeditions. Sung makes a move to leave, but Yoo persuades him to stay. Yoo confesses his aspiration to become a licensed guild master, revealing that he needs to lead twenty raids to fulfill his mission. He also mentions that his father intends to establish a guild for business purposes, seeking an S-Rank Hunter as the guild master and Yoo's brother as the second-in-command.
Sung reminds Yoo of the scarcity of guild masters worldwide, most already committed to existing guilds. He further questions if Yoo's father intends to poach a guild master from another guild, warning that such a move could draw negative scrutiny to his business endeavors.
Yoo extended a portfolio brimming with documents to Sung, detailing a building that Yoo's father had set his sights on as the guild's future headquarters. With a current market value of thirty billion, Yoo generously offered this entire fortune to Sung, contingent upon his assistance in completing nineteen triumphant raids. Sung pondered the proposal deeply but ultimately declined Yoo's generous yet challenging offer. Despite Yoo's persistent attempts to sweeten the deal, Sung made his exit.
Elsewhere, Dongsoo, Hwang's brother, sought information on the two individuals who had accompanied his brother and his men on their fateful raid. A woman named Laura presented Dongsoo with a dossier on the incident. Convinced that his brother had been foully murdered, Dongsoo inquired about the consequences of committing a homicide overseas. After Laura elucidated the potential repercussions and they discussed Dongsoo's schedule, he harbored a grim hope that Sung and Yoo would survive long enough for him to exact his revenge.
As Sung and Jinah embarked on a jog, they engaged in a whimsical conversation about what Jinah would do with thirty billion dollars. Sung's pace suddenly intensified, leaving Jinah in his wake. He accessed the Player Log system and discovered that he had surpassed the running requirement for his quest. Intrigued, Sung pondered the system's upper limits and continued to push himself. He realized that the system had a cap, and notably, his daily quest had transformed into a secret one.
Sung examined the rewards from this enigmatic quest and spotted a "blessed random loot box." With a sense of anticipation, he selected it and opened the box to reveal "The Demon Castle's Key." The item's description revealed that it granted access to an S-Rank dungeon known as The Demon's Castle. Conquering this dungeon would yield the ingredients for the "Elixir of Life," a potion capable of curing all illnesses through potent magic.
With thoughts of his mother's illness swirling in his mind, Sung rushed to the location specified by the Player Log system. As he entered the dungeon, he mentally prepared to use the teleportation stone he had saved from a previous instance dungeon adventure if things took a turn for the worse.
Sung soon confronted a formidable magic beast known as Hell's Gatekeeper Cerberus. Despite his best efforts, none of Sung's weapons, enhancements, or abilities seemed to make a dent in Cerberus's defenses. In a desperate attempt to escape, Sung reached for his teleportation stone, but Cerberus struck, causing him to lose it. Desperate, Sung resorted to the Player Log store and purchased a few potions, which offered only minimal assistance.
As a last resort, Sung remembered the Kasaka's Venom Gland item in his inventory. With a grim determination, he consumed the concoction. Empowered by its toxic strength and his relentless eye-stabbing attacks, Sung managed to vanquish Cerberus. After healing himself, the Player Log system notified Sung of his new unlocks and a small, document-like reward appeared.
The system then informed Sung that he needed to find three items to craft the Elixir of Life, all located within the Demon's Castle. Recognizing the perilous nature of such a venture, Sung acknowledged that entering the castle immediately would be suicidal. The episode concluded with Sung vowing to investigate the castle at a more opportune time.
