Damon Williams

Damon Williams (also known as Yellow Eyed Man) is Satan's second in command, and whose goal was eventually to have his leader being able to be released from the underworld to earth. He has been around observing events in history closely, and was around the time the Harrison's ancestors were hung and found guilty of practicing magic. Discovering about the prophecy of the Power of Four, he made it his effort to stop this prophecy from coming to pass, was responsible for murdering the Harrison's brothers parents, and played an indirect role in their older sisters death.

Determined to test their loyalty and powers, he posed as one of the Harrison Brothers bosses, and would appear often as a hooded man with yellow eyes when he confronted other demons and the Harrison Brothers. However the knowledge that he was evil was not revealed, and covered his tracks as various times, during the end of season 1, he was revealed to be a demon, and the brothers believe he was killed, and to the audience/readers, however we learn that he is still alive later on.

Season 1

 * appears in every episode except 1x5, 1x6, 1x7, 1x10, 1x13, 1x14, 1x18

Season 2

 * All Hell Breaks Loose Part 1 - 2x23 (flashback)

Season 4

 * 4x23
 * 4x24 

Season 5

 * 5x1
 * 5x2
 * 5x10
 * 5x15
 * 5x16
 * 5x19
 * 5x21
 * 5x22
 * 5x23

Season 6

 * 6x8
 * 6x10
 * 6x17
 * 6x19
 * 6x20
 * 6x21
 * 6x22
 * 6x23

Season 7

 * 7x23

Season 8

 * appears in every episode except 8x2, 8x5, 8x6, 8x7, 8x11, 8x12, 8x13, 8x14, 8x17, 8x19

Season 9

 * Magical History Lesson - 9x12 (flashback)
 * Till Charmed Do Us Part (Part 2) - 9x24 (In the past)

Trivia

 * He is the longest serving antagnaist on the series, and has appeared in every season but season 3.
 * It took The power of four 3 times to finally vanquish him, once during season 1, once during season 6 and finally season 8.
 * He appeared as a main character during seasons 1 and 8, a guest star during season 2 and a special guest star in seasons 4, 5, 6, 7 and 9.
 * Damon appears in every single season final, except season 2 and 3.