Help identifying giant blue LEGO Bionicle set I have what appears to be a giant Bionicle. The head is the size of a small human head almost the size of a mask. 

It is blue in colour and in 5 bags. It looks like more than 100 pieces. The instructions and box are lost. No idea what it is. 

Any ideas? Can post pics if needed.
Gadunka (8922) came somewhere around 2007, and was part of the underwater themed bionicle sets. When assembled it is quite big. Maybe this is set you were looking for?