Mask of Light and Shadow

The Mask of Light and Darkness was a Kanohi which was created along with Takutanuva. It had the powers of both the Kanohi Kraahkan and the Avohkii. It split back into the Avohkii and the Kraahkan as Takutanuva split into Takanuva and Teridax.

Trivia
In the movie, the mask was half Avohkii, half Kraahkan. In the set, it was the Kraahkan. In Bionicle: The Game, it was the Avohkii.