The UFC's definitive -- and debatable -- list reaches the top ten. See who takes the top spot in this ranking of all-time greats as determined by statistics, historians, media, fighters and fans.

Countdown of the next 20 competitors to ever step foot in the Octagon, as determined by statistics, historians, media, fighters and fans.

Countdown of the next 30 competitors to ever step foot in the Octagon, as determined by statistics, historians, media, fighters and fans.

Countdown of the next 50 competitors to ever step foot in the Octagon, as determined by statistics, historians, media, fighters and fans.

Countdown of the next 50 competitors to ever step foot in the Octagon, as determined by statistics, historians, media, fighters and fans.

Countdown of the first 50 competitors to ever step foot in the Octagon, as determined by statistics, historians, media, fighters and fans.