If you go to summary on the Pokémon it says this Pokémon is pretty "whatever it says here" what is the best option?
Adamant or Jolly but I'd say Adamant is better.
Adamant is best because Natures lower one stat and raise another. Palafins best stats are hp and speed. But it's other stats are kinda low. It's best attack stat is physical attack. Adamant nature raises this to be higher and lowers its worst stat which is special attack. Jolly is the next best option because it raises Palafins speed stat and it already has amazing speed. And it lowers the worst stat which, again, is special attack. Adamant is best. Jolly is second best. If you wanna change it you have to catch a new one, or make it have babies and hope one hatches with the nature you want or use a certain item called a Nature Mint.