4x12 - Teen Titans

Robin, Starfire, Cyborg, and Beast Boy awake to a nightmare. Trigon has risen and he has ended the world. Every building is destroyed, and all life has been turned to stone. Due to one last gift of Raven's, the Titans have survived. Now, they must find a way to get Raven back, maybe she knows of a way to stop Trigon. But to do this, the Titans will have to accept help from their old enemy - Slade.