How do you get past the Fish Monster Swamp?

You talk to Master Utan, and he gives you poison apples, which you put on your fishing hook. You will eventually catch King Marden.

Here's the long answer (depending on how far you've gotten). Fish Monster Swamp has 3 sections. Section 1 has a swamp on either side and several dwarfs lying on the ground. Section 2 has a huge swamp. Section 3 has Master Utan (who looks like a huge ape) sitting on the ground.

1. In Section 1, talk to the Dwarf sitting on the log. Give him the Grape Juice from your items and he'll give you his fishing pole.

2. Continue past the big fish swamp to Master Utan in Section 3(take his picture; he's an Inside Scoop!) and talk to him. Pick up the poison apples next to him on the ground after your conversation.

3. Go back to the big swamp in Section 2 and walk right up to the edge. Monica will tell you to fish with the poison apples. Put one on your fishing pole as bait & you'll catch King Marden (he's another Inside Scoop).

4. Go to Section 1 and catch a Priscleen (use either battan, mimi, or prickly for bait). Take it back to King Marden; he'll release the dwarves from his spell.

5. Go back to Master Utan, and this time he'll move the big rock so you can continue through the dungeon path.

You have to use a poison apple to catch the fish and then the fish will tell you to catch a fish to clean it