Natures are sort of like a Pokémon’s personality. But it’s more than just for show. A Pokémon’s nature also works as a bane/boon system. Every nature gives a Pokémon a stat boost while also giving the same Pokémon a nerf in a different stat. If players want to min-max their Pokémon, the right nature is critical. And the first Pokémon players get in Pokémon Scarlet and Violet is their starter Pokémon. Having the right nature on the starter pokemon is vital for optimal progression. With that said, here is the best Nature for the Fire-type starter Fuecoco and its evolutions, Crocalor and Skeledirge, in Pokémon Scarlet and Violet.
Modest or Quiet
The neat thing about Pokémon is that it can be enjoyed by everyone. Players that want to play the game casually can go through the region, play through the story, catch their favorite Pokémon and have a good time. But for players wanting to use Pokémon as a competitive outlet, there is a ton of depth in the game when it comes to its battling system. Out of all the things players can do to gain an advantage over their opponents, one of them is making sure they have the right nature on their Pokémon.
With the Fuecoco line excelling in special attack while already having a poor speed stat, the best nature to have on Fuecoco — and eventually Skeledirge — is Quiet. A Quiet nature buffs special attack and lowers speed; with Skeledirge already having a low enough speed that will make it go second every turn, it’s best to lean into the Pokémon’s power and rely on its bulkiness to win trades.
There are other good natures too. Modest is arguably just as good if not better since special attackers will almost never have physical attack moves making the attack stat actually useless. Modest adds special attack at the cost of attack. This might be better as at least the speed stat is usable. But if there is a world where players want to have some sort of physical moves on Skeledirge, then go with Quiet.