The Crystal Serpents were four huge Rahi which dwelt in four different corners of the island of Artakha. They attacked and defended themselves by maneuvering their crystalline bodies to focus light into devastating heat rays. They were dormant most of the time, awakening to feed once every century or two.
It was said that at the dawn of time, Artakha decided that he could create Rahi as easily as masks or weapons. In his first and last attempt, Artakha created four great crystal serpents. Unlike other creatures which attacked prey by biting or crushing it, the crystal serpents maneuvered their crystalline bodies to focus sunlight into a lethal heat ray. Realizing that they could not be tamed, but not wanting to destroy his creations, Artakha set them free and abandoned trying to create living things. The four serpents migrated to four separate parts of the island of Artakha, occupying the northern, eastern, southern, and western sections. They were dormant most of the time, sleeping underground or in the shade of great boulders. It was believed that they only need to wake to feed once every two centuries or so. They did not prefer to prey on Matoran, but the Matoran considered it wise to avoid them when they were active.