New lasers with new mechanics and functions in Portal 2: Episode One.
It works the way that those Portal 2 Lasers do, they hurt you when you touch them, and can be reflected into other directions with the Reflection Cubes, but it's different! They can be different colors, only being able to power a Laser Catcher of the same color of the corresponding laser.
The lasers can be combined together to make a laser of a different color by using two lasers hitting a Laser Combination Cube.
Also for rave parties!