Requirements: For this quest you will need Swamp Paste, which can be bought in Port Khazard. You will also need level 30 Firemaking.
Rescue Mission-
To start Sea Slug speak to Caroline who can be found in the Northern edge of Witchaven. Agree to go check up on her husband at the fishing platform and she will tell you to ask Hogart to take you there. Speak to Holgart, who is standing nearby, he will tell you that he needs Swamp Paste to repair his boat. Give some to him and he will repair the boat, then speak to him again to get a ride to the platform.
Marooned-
Now head to the North-East corner of the platform and climb the ladder. Head to the room on the west side and talk to Kennith through the boxes. Kennith will tell you that his dad left for help days ago. Go back and speak to Holgart and he will take you to a small island where Kent is marooned. Speak to Kent and he will tell you about the sea slugs mind controlling powers, then ask to go rescue Kennith. He will then proceed to pull a sea slug off of you.
Need a Light?-
Have Holgart take you back to the Platform then try to climb up the ladder again, a fisherman will stop you. Head to South-West building and speak to Bailey, he will give you a torch to scare the slugs with. Grab some broken glass off the floor in his room and head back to the ladder. Grab some damp sticks off the ground and use the broken glass on them to dry them. Now choose the rub-together option on the sticks to light the torch.
A Happy Ending-
Now climb up the ladder and go talk to Kennith again. He refuses to come with you so you have to find another way to get him home. Go outside of the building and kick the boards on the wall of Kenniths hiding spot. Speak to Kennith again then go to the Crane next to the building. Use the controls to rotate it and Kennith will climb onto the crane then get lowered to safety. Speak to Holgart to head back to shore then talk to Caroline to complete the quest!
Rewards: 1 Quest Point 7,175 Fishing Experience An Oyster