[thephantomcredits]

If its anyone who was alive and active in the third age, this would be my list:
1. Sauron - No explanation Necessary
2. Gandalf the White His Skill and Mind Bested Sauron
3. Gil Gilad - Fought Sauron Face to Face
4. Saruman The White - Pretty effective at putting together a force to make war and imprisioned The grey pilgrim.
5. Gandalf the Grey - Dispatched the Balrog, set the wheels in motion
6. Balrog - Powerful leftover from a another age
7. Galadriel - The Thingol of the Third age. Keep Lorien a safe have and a ringbearer.
8. Radagast - He's still an Istari
9. Elrond - Well rounded Elf
10. Aragorn - In the line of Numenor, long life, great in battle.
Honorable Mention:
Treebeard, Beorn, Glorinfidel, The nine wraiths, Witch king
Note: If you think Gandalf should only be mentioned once The Witch King would move up, but since his power was so tied to sauron I didn't feel he belonged in the top ten, Also Shelob Is just a beast, a well prepared troop of soldiers with the right equipment could eliminate her.