DYSMANTLE

The fish that counts toward this achievement is called a Namazu; it is depicted as bug-eyed and with a gasping mouth; it is blue-green with a silver back. When you catch one, the words "What a great catch!" appear above your character's head.

Getting this fish seems completely random; I went through a lot of fishing holes without catching one and in the SW desert region I caught two in one hole.

The other fish that can be caught are:
- Common Roach (a blue-white fish with yellow fins/tail)
- Red Herring (a red fish ... no real surprise there)
- Superior Salmon ( a purple-ish fish with yellow underbelly)
- Zany Zander (a green fish with yellow mottling)

This will take quite some time as the legendary fish are very rare. After you invent the fishing pole, you can fish at any of the spots on the map marked with the fish icon for guaranteed fish to be caught, however they are random what you get. I got my fifth legendary fish to show up after exploring the map roughly 90% completed. Just keep at it and you will get it. I always swapped to the Tackle and eventually had the Fishing skills from level ups as well to increase fishing speed to make it less a hassle.