In Pokemon, it's important to know what each nature raises and lowers and which ones are more compatible with certain competitive roles.
Natures are an oft-overlooked aspect of playing Pokemon, at least in a casual playthrough. It’s a different story with competitive battling, though; having the right nature is a bit of a make-or-break situation that determines how well Pokemon can play certain roles.
Natures raise one stat and lower another, and it’s important not only to know what each nature raises and lowers, but which ones are more compatible with certain competitive roles. Knowing how they function in conjunction with certain Pokemon helps, so with every entry, alongside explaining the significance of the nature in question, an example will be given of a Pokemon that’s at its best with said nature.
Adamant raises the Pokemon’s Attack stat and lowers the Special Attack stat, and that’s a perfect nature for a meta where you’re usually expected to stick to one category of attack anyway. Physically offensive Pokemon could also have a Jolly nature to increase Speed instead of Attack, but Adamant is better if you’re not worried about winning the Speed battle.
This is the case with most wallbreakers, who are usually faster than the walls they’re trying to break. For example: in Generation VIII’s OverUsed (OU) metagame, Rillaboom really puts the Adamant nature to excellent use, not really needing a Speed raise from Jolly since it usually uses a priority move. Therefore, you’re left with a priority STAB Grassy Surge Grassy Glide that’s optimized to hit as hard as possible. Dracovish also benefitted quite a bit from this before it got banned to Ubers.
Modest is the polar opposite of Adamant, in that it raises Special Attack and lowers Attack. Granted, that fulfills the same role in terms of functionality: making sure your Pokemon’s attacks hit as hard as possible. As stated, this works great with wallbreakers.
One worthy candidate of running with a Modest nature is Primarina. The Alolan Water-type starter works best as a wallbreaker; it’s slow, can take a lot of special hits, and has a Special Attack that, when boosted with the Modest nature and perhaps a pair of Choice Specs, can put a dent in even the best defensive Pokemon. Other relatively slow, special attacking Pokemon this works great with include Nidoking and Magnezone.
As alluded to, if you’re more inclined to give your physical attacker a jolt of Speed, a Jolly nature (+Speed, -Sp. Atk) is the way to go. Giving the right Pokemon the Jolly nature can give it a little Speed boost that could ensure you out-Speed most other Pokemon. For example, Excadrill works excellently as a sand sweeper, since it already has an awesome 134 Attack stat, and its Speed stat, EV-maxed, optimized by the Jolly nature, and doubled by Sand Rush, beats some of the fastest Pokemon in OU.
However, it’s not just purely offensive Pokemon that benefit from a Jolly nature. Certain types of utility Pokemon, such as hazard setters and suicide leads, could benefit from a Jolly nature, ensuring that they’re able to execute either Stealth Rock or Explosion, respectively, before their opponent finishes them off; Mew can run a Jolly set with these moves since it has access to all of them.
The special variant of Jolly, Timid raises Speed and lowers Attack. When given to a very good special attacking Pokemon, that little extra Speed can prove to be huge. Case in point: the pseudo-Legendary Hydreigon. While it has an excellent Special Attack at 125, that 98 Speed might leave something to be desired. Therefore, with the help of a Timid nature and maxing out its Speed EVs, Hydreigon manages to put its hat in the ring of the fastest and best offensive Pokemon of OU.
Timid could work on a wallbreaker set, though you’d want to reserve it for the mid-to-high Speed Pokemon rather than the slower tanks that benefit from a Modest Nature. Tapu Lele, for example, works great with a Timid nature and a pair of Specs.
Unlike its relationship with offensive stats where you should optimize one offensive stat most of the time, a nature’s relationship with defensive stats can kind of work both ways. You could choose to bolster one particular defensive stat to the best of its ability, or improve the lesser one to make the Pokemon a more all-around wall. Regardless, if you’re looking for physical Defense, either Impish or Bold work for you, reducing Special Attack and Attack, respectively.
For example: Toxapex, a Pokemon with excellent physical Defense, is very often seen with one of these abilities. On the contrary, Chansey and Blissey have such terrible physical Defense that it makes giving them one of these abilities somewhat necessary. Determine your ability to predict incoming physical or special attacks, and pick your poison.
Of course, there’s the special side of things; Careful and Calm raise Special Defense, reducing Special Attack and Attack respectively. These are much more commonly seen in OU, with most of the best defensive walls being physical ones desperate for a boost on the other end.
A great recipient of the Careful nature is Hippowdon, a Pokemon with excellent Defense and a physical attacker. Its Special Defense lags behind quite a bit, and the Careful nature proves to be quite helpful for it. On the other hand, a Pokemon like Heatran boosts its Special Defense while keeping its Special Attack regular with the Calm nature.
These two natures are pretty weird and somewhat rarely used. They raise a defensive stat–Defense and Special Defense respectively–while dropping Speed. It makes sense, as it’s the walls that really have the least use for a good Speed stat.
However, where these two natures see the most use in particular is with pivots: Pokemon that take a hit, then switch out. Pokemon like this really don’t have a use for a Speed stat, since a move like Teleport always moves last, and even if you’re using a move like U-Turn or Flip Turn instead, it’s best to just take the hit before a weaker, less defensive Pokemon does. In Generation VIII OU, Pokemon like Slowbro and Swampert thrive in this role, going for the Relaxed and Sassy natures to raise whichever stat the user sees fit.
These are two more Speed-dropping natures, this time raising an offensive stat: Attack for Brave and Special Attack for Quiet. While these are even rarer than sets with Relaxed or Sassy, they might be more fun to work with when you’re using a certain type of team: a Trick Room team. The lower your Speed stat in a regular setting, the higher it is in Trick Room, so your nature is essentially raising two stats if you can get it set up.
Hatterene is unquestionably the best candidate for a Quiet nature thanks to its great Special Attack and appallingly low 29 Speed. Meanwhile, the Ubers tier has Ice Rider Calyrex running with a Brave nature when it’s running a Trick Room set. An honorable mention goes to Gyro Ball users, who also benefit from lower Speed thanks to Gyro Ball being stronger the slower the user. Steelix can put a Brave nature to excellent use with a Gyro Ball set.