Megalodon

From IdleOn MMO Wiki

Can be obtained by catching the MGredfish.png Megalodon in the Fishing Minigame, which appears upon catching two MGbluefish.png whales, and purposely missing the 3rd, as stated in the The Bobber Challenge Scroll.png The Bobber Challenge Scroll. MGbluefish.png Whales appear after catching 9 fish in a row without missing in the minigame.