1. Jon Jones
Anderson Silva is well-regarded as the greatest of all time, but if he were to fight Jon Jones, I think Jones would take that fight. He will use his reach to keep away from harm, get takedowns, and land strong ground and pound. Silva is very hard to finish, but a decision for Jones is very possible. We may have a chance to see this fight if Silva defeats Chris Weidman.
2. Anderson Silva
An unbelievable 16 and 0 in the UFC with an astounding 10 title defenses. Anderson Silva has pulled off the unimaginable so many times in the cage.
3. Georges St-Pierre
Two time UFC welterweight champion with 8 defenses of his title. GSP is the greatest welterweight of all time.
4. Jose Aldo
Aldo has been untouchable at 145. He has won 15 in a row and hasn't lost since 2005. However he has a very tough test in Anthony Pettis coming up. I actually think Pettis will win that fight and jump into the top five, but only time will tell.
5. Ben Henderson
The best 155er in the game right now, Ben Henderson finds ways to get the W every single time in the UFC Octagon. In eight months he has defended the UFC lightweight title three times.