It's a spell, cast by a noob. It petrifies.
Later on when facing the O, the C steals the ability.
The full casting line of the spell is "Basiliske Galete meta Kkt Podn kai Kakoin Ommatoin Pnon Tou Iou Ton Chronon Parairousan! Pno Petras!".
It is a reference off of a petrification spell from Negima.