Sammael
Sammael was one of the Forsaken who was most jealous of Lews Therin. Before he turned to the Shadow, they would compete in everything, from stones, to dueling, to using the Power. Lews Therin almost always won, but Rand remembered one of Lews Therin's memories of the one time Sammael won at stones and he bragged to everyone that he beat Lews Therin. He refused to have a scar across his face Healed that Lews Therin had given him because of his pride. He also wanted it as a constant reminder that he would exact revenge on Lews Therin one day. Upon being freed, he took over Illian, and tried to make an alliance with Rand that neither would attack each other for right now. Rand refused and invaded Illian with soldiers and Asha'man. Sammael fled the city to Shadar Logoth, formerly Aridhol, and was supposedly killed by Rand with balefire, although Rand never saw him die, and those Forsaken can be pretty tricky with death.