Giant Squid - These giant beasts have 6 small arms and 2 extendable ones near the front.
Giant Crab - These crabs have enormous claws and almost impenetrable shells. It takes a lot of hits to kill it.
Pufferfish - This fish normally remains at normal size but don't get too close because it can expand its body.Oddly enough it cannot be destroyed by whirlpools.
Storyline
Gallery
The Giant Crab monster
The Giant Pufferfish monster
The Giant Squid on the cover of the Skullduggery Island Book
The Giant Squid monster
Trivia
A similar crab monster can be seen in the Ice Age 4 Ad.
Many of these sea monsters will attack you continuously if you head to the top-left corner of the screen.
You can kill them by either using your canons or sailing to Golden Harbour and making them crash into the rocks.