Brinelake Dock can be found near the Taco Basura.
Before one can even think of facing off with the Gorged Tumor, the player needs to have the Diamond Scale equipped.
At the end of the mermaid-infested waters of Brinelake, the Gorged Tumor Resides. The fight will be long and brutal.
Punches and Anar-chi prove to be not as useful as they should be underwater, so you'll have to rely on the harpoon guns that spawn from above (using Anar-chi as much as possible is still absolutely recommended.) Stay as far as possible and feel free to get trigger happy since the harpoon guns are unlimited, not the ammo. The Gorged Tumor hits hard and inflicts lethally potent poison, fortunately his big size gives you a lot of room to hit. Use the water's effect on your jumps to evade hits from both the Tumor and the mermaids that accompany him. Keep hitting him with harpoons and Anar-chi until he bleeds to death.
- A useful tactic for in between Anar-chi hits and picking up harpoon guns is to jump from one side of the tumor to the other while throwing a barrage of punches.
- Being inside the tumor (Standing where it is, which is easy to do due to its massive size) is a good place to use whatever move you can, but be careful, as it will leech your health.
- Whenever you get the chance, use your team attack. It is by far the most useful tool against this mountainous monstrosity.