So I devised a system taking into consideration 3 criterion: - # of defenses - # of wins against other champions - recency of championship The first two criterion are self explanatory. I decided to add the last criteria to give more weight to more recent champions because the sport does evolve. Meaning, winning against current contenders will be harder than the past and should be taken into consideration. I also included interim champions. While some may disagree, these are the three arguments I see being used to justify rankings time and again on this board. All I did was combine them. Here's the ranking that resulted: 1. Khabib 2. Edgar 3. Penn 4. Dos Anjos 5. Henderson 6. Ferguson 7. Alvarez 8. Pulver 9. Pettis 10. Poirier 11. McGregor 12. Sherk Feel free to critique specific rankings and I'll try to explain why my system put them above or below certain ranks. Edit: I forgot that Pulver had a win over Penn. Including that moved him up above Pettis, Poirier and McGregor.