The Krahka is a BIONICLE combiner model introduced in 2004. It can be built from the pieces of all Toa Metru sets. The instructions for this model were originally only available from the last pages of the book BIONICLE Adventures 3: The Darkness Below, however this version was coloured black and white, making it hard to discern the colours for a specific piece. The book BIONICLE: Rahi Beasts later provided an image of Krahka with the actual colours.