The One That Got Away
70 (Requires 70)
is a surprisingly quick bottom feeder found in the waters of Nagrand. They grow their entire lives and are well known as fighters.
Years ago, I caught what I'm certain was the world's biggest mudfish... until it snapped my line and escaped.
A fisherman of your caliber doesn't need to be told what to do—your destiny awaits in the lakes of Nagrand.
Tell me you caught him. Please tell me you caught that son of a carp.
There he is! I'd know that scar anywhere.
To be completely honest, I thought he'd be... bigger. Well I suppose I'll let him go and try again another day.
The quest log is somewhat vague about this, but the can only be caught in the waters of Lake Sunspring or Skysong Lake. Fishing everywhere else will get you lots of fish, but not the fish you're looking for. Check your minimap subzone readout to make sure you aren't in Garadar or another inappropriate location which appears to be on the lake shore, but does not count for the quest.
Also, World's Largest Mudfish does not need to be fished from a Mudfish School.