Used to fish up Karkinos while in posession of Smouldering Crab Shell at any of the lakes in Abyssea - La Theine.
(Appears to be) a 100% drop from Poroggo Dom Juan; should be noted that he is an easy kite fight, while he does have movement +, he spams low tier Poisonga and Waterga almost every time he is in range, allowing distance to be gained.