Gadunka

Gadunka is a villain in the Lego BIONICLE series. It was once a small Rahi before it was unwittingly exposed itself to the Kanohi Ignika's energy, thus transforming into a large, vicious monster.

History
When Nocturn placed the Kanohi Ignika onto the seaweeds, a lone Gadunka scurried under the mask for shelter, unknowingly exposing itself to the mask's energy. The energy then transformerd Gadunka into the form of the monstrous creature.