Based on what? Every single competitor here has better 1v1 feats than Leonidas. Leonidas was a good general who functioned best in group combat. His 1v1 feats don't match up to the rest.
Leonides is low-range superhuman. Spartacus is too iirc. Maximus is human, but a total bad ass. If any of these three tried to solo take the beach of Troy like Achilles did, they'd have taken an arrow to the knee.
Achilles is legit superhuman. Hector who was a great fighter only managed to get one glancing blow and Achilles was likely playing with his meal the whole time.
Achilles should be able to take them all out 3 vs 1 if he's not playing around.