Dreams in B/W and Color and Elijah

I've heard from some places that dreams in black and white are from the enemy, and dreams that have color are God-annointed. My son had an alarming dream that he believes is phrophetic. He says it was all black and white until the very end when he saw a blue screen with a scrolling line at the bottom that says "This message brought to you by Elijah."  The dream was very exact, descriptive and problematic. This is the second dream he's had that seems to be God-annointed. He was filled with "fear, dread and doom" when he woke and "knew the dream was prophetic". Any opinions, about the B/W switching to color and about the Elijah part would be helpful. I feel his dream is significant and believe Elijah is likely one of the endtimes 2 witnesses, so...thanks.