1. Kharn the Betrayer 2. Doomrider 3. Lufgt Huron 4. Kor Phaeron 5. Luther the Arch-Heretic "MAIM! KILL! BURN!"
Well, Magnus and Ahriman. Because they really did get the shaft and get betrayed, unlike most of the other Traitor Legions. Everything they did, they first did for self-preservation... and now they do it for legit revenge. Lucius the Eternal. Because, seriously, go ahead and kill him. Watch what happens. Perturabo. IRON WITHIN! IRON WITHOUT! And for my fifth, hmm... Eliphas the Inheritor. In games marred by horrifying voice acting (SPHESS MAHREENS! MEHTUL BAWKSES! SIIINNNDRIII!), Eliphas's voice was like having sex with my speakers. Audiophilia. My Gods, what a sexy voice. I nearly started a real-life cult, just to see if I could summon that magnificent bastard. Please note how all of these are Traitors.
1. Huron Blackheart. He did the best he could for the Imperium, and was fit to turn his sector in to one of the safest in the Imperium. They refused to let him and wouldn't look at the long picture, after he tried to do it anyway (sending partial tithes, to show he was still loyal). They tried to kill him, and now he's out for revenge. And on tabletop he can give terminators and their dedicated land raider infiltrate. 2. Ahriman. I like the whole betrayed theme they have going on. 3. Cypher. 4. Alpharius/Omegon. See a theme here?