![Ladybird LEGO Atlantis Activity Books](http://1.bp.blogspot.com/_qa13GlKvkqY/S8pdRhaCOHI/AAAAAAAAAaM/hBJ9LEm1Mbk/s200/Ladybird-LEGO-Atlantis.jpg)
Although the Shark Warrior is easy enough to come by at reasonable prices, the Squid Warrior from The Gateway of The Squid (set 8061) currently averages $12.69 USD on BrickLink. It even comes with a trident!
Click on over to Brickset for more details.
(Picture from Amazon UK)