I was just fishing, how did I become a Great Old One?

Urban martial arts | Cthulhu | Dihua style | Invincible | Lighthearted and humorous | Simulation | Pretending to be weak while actually being strong | System (hidden)
In order to earn money for her mother's expensive medical expenses in the ICU and to raise enough tuition fees for her younger sister who is in college, Jiang Li has done a lot of jobs.
Drug test participant, house cleaner in haunted houses, midnight deliveryman...
This time, upon hearing that fishing in "Blackwater Bay," a place outside the city surrounded by barbed wire, could fetch five thousand yuan for a single fish, Jiang Li took a fiberglass fishing rod from Pinduoduo that cost nine yuan and ninety cents with free shipping and went there.
However, the water here is a bit deep.
A strange fish with a human face, an octopus chanting sutras underwater, a giant shadow that only dares to surface on stormy nights...
Jiang Li battled against these "big fish" with his ever-burning fishing line.
"Damn, this fish is really strong; it'll definitely fetch a good price!"
What he didn't know was that these "large cargoes" had a common name in the outside world—**the indescribable old relatives**.
Upon arriving in this body of water, they are no longer synonymous with fear, but have become braised ingredients and steamed ingredients in Jiang Li's bucket.
The spiritual essence they retained after their deaths became part of Jiang Li's body, enabling him to achieve physical sainthood and solidify his sanity.
Until one day, an ancient god in the deep sea awoke and sought to devour the world.
However, the moment it surfaced, it saw a man sitting on a cloud, holding a fishing rod formed from the Milky Way, looking at it with excitement:
"Holy crap! How many pounds does that weigh? This is outrageous, guys!"
At that moment, the ancient god finally remembered the fear of being dominated by the fisherman.