How do I find all legendary fish for the story-related side mission?

To find all legendary fish in Red Dead Redemption 2, you must first unlock the ''A Fisher of Fish'' side mission. This mission becomes available in Chapter 3 after meeting Jeremy Gill, a fisherman who lives in a cabin near Flat Iron Lake. He will give you a map marking the locations of 13 legendary fish scattered across the game world. Each fish requires specific bait and fishing techniques to catch, so preparation is key.\n\nBefore starting, ensure you have the Special Lures, which are essential for catching legendary fish. These lures can be purchased from the bait shop in Lagras, located in the Bayou Nwa region. You will need the Special Lake Lure, Special River Lure, and Special Swamp Lure. Without these, you cannot catch legendary fish. Additionally, equip a high-quality fishing rod, which you acquire during the main story mission ''A Fisher of Fish.''\n\nEach legendary fish is found in a specific body of water, and the map provided by Jeremy Gill will guide you to their general locations. For example, the Legendary Smallmouth Bass is found in O''Creagh''s Run, a lake in the Grizzlies East region. To catch it, use the Special Lake Lure and cast your line into the deeper parts of the lake. Pay attention to the fish''s movement patterns and reel it in carefully to avoid breaking the line.\n\nSome legendary fish are more challenging to catch due to their size or the environment. For instance, the Legendary Longnose Gar is found in the swampy waters of Lagras. This fish is aggressive and will fight hard, so be prepared to use the Special Swamp Lure and maintain tension on the line. If the fish swims into vegetation, avoid reeling too quickly, as the line can snap.\n\nAfter catching a legendary fish, you must mail it to Jeremy Gill using the post office. Each fish you send will unlock a reward, and catching all 13 will complete the mission. However, you cannot store legendary fish in your satchel, so make sure to visit a post office immediately after catching one. If you lose a fish, it will respawn after a few in-game days, so don''t worry about missing your chance.\n\nPractical tips for success include saving your game before attempting to catch a legendary fish. This allows you to reload if something goes wrong. Additionally, use Eagle Eye to spot fish in the water, as it highlights their location. Finally, be patient and avoid rushing the process, as legendary fish require precision and timing to catch.\n\nIn summary, finding all legendary fish involves unlocking the mission, acquiring the right lures, and using proper fishing techniques. Follow the map, prepare for each catch, and mail the fish to Jeremy Gill to complete the mission. With patience and practice, you''ll become a master angler in Red Dead Redemption 2.