Farming each week:
- Lich King - Invincible's Reins - 6 runs each week
- Yogg-Saron - Mimiron's Head - 6 runs each week
- Alysrazor - Flametalon of Alysrazor - 3 runs each week
Farming from time to time:
- Bloodlord Mandokir - Armored Razzashi Raptor
- High Priestess Kilnara - Swift Zulian Panther
- Altairus - Reins of the Drake of the North Wind
- Al'akir - Reins of the Drake of the South Wind
Don't think I farm more mounts, since I've all off them already (Except Ultraxions Mount).