Eldritch Cone

Greater Invocation; 5th; Blast Shape
This blast shape invocation allows you to invoke your eldritch blast as a 30-foot cone. The eldritch cone deals the normal eldritch blast damage to all targets within the area. This is not a ray attack, so it requires no ranged touch attack. Any creature in the area of the cone can attempt a Reflex save for half damage.

Source: Complete Arcane