Ice is the element of the Hypnobrai tribe of Serpentine. Although the Hypnobrai, along with the other Serpentine, have no direct connection to any elements in the Ninjago animated series, each tribe has a dominate element on their Spinjitzu cards. For the Hypnobrai (Rattla, Mezmo, and Slithraa), ice is the dominate element of their Spinjitzu cards. This is also hinted in the environment of the Hypnobrai tomb, as it is a system of ice caves.