The Statues appeared as average statues, making them hard to identify around normal statues.
The Statues use a unique and nearly-perfect defense mechanism - quantum-locking - which caused them to turn into stone when being observed. It could also be done at will, when they believed they were being watched. When not being observed, they could move incredibly fast to catch their victims.
They could also feed on types of energy, such as the radiation given off by a nuclear power plant or the electrical energy in electronics. This also caused lights to flicker, making it easier to avoid quantum-locking.
When quantum-locked, the Statues would still be awear of their surroundings.
These Statues also have the ability to infect normal statues with the Statue virus; a decease that turns any stantue into a Statue That Walks But Never Moves. It is hinted that this is how the species breed.
When being observed, the Statues' skin becomes as hard as stone. This provents them from moving, but also makes them indestructable.
However, should their opponent 'fires blind' at them, the Statues would become volnerable and and most likley be injuried/killed.