Hello o/ The Mystical Fish is a -very- rare fish that can be fished once you reach guru1 fishing level. There are 5 different fishes that can only be caught in 5 different, specific locations. 1. North Margoria 2. Central/South Margoria 3. Hotspots/Seagull Spawns 4. Central/Middle Margoria 5. Velia/"Coast" Once all 5 are cought they can be combined to create an item which allows you to summon the world boss Vell once. You also get a quest which allows you to select 1 out of three rewards. 1. Silver item worth 300m when sold. 2. "God of Fishing" Title 3. Unique fishing float sub-item Best of luck on your fishing quest! o/