The Fire-type is usually known as one of the strongest types in Pokemon for good reason. It has five resistances, the second-most out of any type, and an array of both physical and special attacking moves. However, it's best used when paired with another type.
Some of the best Fire-type Pokemon are dual-typed such as Blaziken, Heatran, and Volcarona (mainly due to their extra STAB options). But what about those Fire-types without a secondary typing?
It hurts not having that secondary STAB and Fire is one of the types that is most susceptible to Stealth Rock damage. Still, these ten Pokemon have gained some usefulness as the best mono-typed Fire-types in the game. Some still aren't as good as their dual-typed counterparts, but others have gained nice viability that transcended their pure-typed status.
10 Generation V: Simisear
Its status as "Japan's least popular Pokemon" notwithstanding, Simisear has dominated the lower tiers of competitive battling. It's locked up a role there as a Fire-type special sweeper since its introduction in Generation V.
It's got a good movepool to go alongside its solid offensive stats -- namely 98 in both Attack and Special Attack, and 101 Speed. It's decidedly more apt as a specially offensive player, though, as it has access to more moves that help that role. Players can set up with Nasty Plot, use Fire Blast for STAB offense, or Grass Knot and Focus Blast for coverage. It can't take a hit to save its life, but when set-up, it can deal great damage.
9 Generation II: Typhlosion
The Fire-type Johto starter proved to be a solid follow-up to Charizard in terms of popularity and marketability. No such luck from a competitive standpoint, though, despite having the exact same stat spread as the Fire-Flying type.
Suffice it to say, the secondary Flying-typing gives Charizard many benefits that Typhlosion doesn't have. Chief among said benefits is the learnset. Charizard's array of coverage moves has proven to be much wider than Typhlosion's. In fact, Typhlosion's only truly viable movesets today all rely on Eruption which, while potent, is very predictable.
8 Generation I: Rapidash
In its day, Kantonian Rapidash was an excellent Fire-type attacker -- especially in Generation I with its Speed-to-critical-hit mechanics. Those were simpler times when you could just set up with one Agility and let 'er rip. Sadly, times have changed.
Since its first appearance, Rapidash has seen mixed results in terms of its viability as faster and stronger alternatives have appeared. With a better base stat total, perhaps it would be much more viable in the current metagame (especially with its decent coverage moves such as Wild Charge and High Horsepower). Alas, while 100 Attack and 105 Speed are nothing to scoff at, other Pokemon play the fast physical attacker role much better.
7 Generation IV: Magmortar
While Magmar was quite solid prior to Generation IV, the evolution it gained in the Sinnoh region, Magmortar, has spent most of its existence roaming around in lower competitive tiers. Granted, it has dominated its competition there. That's mainly due to its combination of bulk and offensive firepower.
While it's incredibly frail on the physical side, it has a solid Special Defense of 95 that can be complemented well with an Assault Vest. It has much more shine offensively despite its mediocre 83 Speed with its nice array of STAB and coverage moves. It's got OK abilities, though both Flame Body and Vital Spirit can be quite situational.
6 Generation V: Darmanitan
While it can't stand up to its Ice-type Galarian form that's literally been banned to Smogon's Uber tier, the original Darmanitan has consistently been a solid option for Fire-type offense. Its main conceptual gimmick is its Zen Mode ability that, while interesting, is counter-productive for competitive purposes as it prevents users from fully committing to either a physical or special Attack.
As such, players opt for its other ability, Sheer Force, instead. This gives it much more potential as an offensive threat given moves such as Flare Blitz, Rock Slide, and Hammer Arm. That works in tandem with its nice 95 Speed and huge 140 Attack stats -- the former of which can be boosted further with a Choice Scarf.
5 Generation I: Arcanine
For the most part, Arcanine has remained steady as a very good offensive Pokemon for a long time. It had quite a long stint in Smogon's UU tier -- a tier just below the premier leagues of competitive Pokemon.
On most days, it's an incredibly potent physical attacker with great Attack power and decent Speed to boot. Most standard sets equip it with Flare Blitz for STAB, Wild Charge for coverage, and Extreme Speed for cleaning up. There are other, more outstanding options in the current metagame, but Arcanine will probably be a mainstay for as long as its exact role isn't taken over by another Pokemon.
4 Generation I: Ninetales
While its Alolan counterpart has seen many an appearance in competitive battles due to its rarity as an Aurora Veil setter, Kantonian Ninetales had seen similar popularity as a sun-setter. Unfortunately, its time as the prototype of that niche has long gone.
By Generation V, it had gained Drought as a hidden ability and was the only fully-evolved Pokemon to have it besides Groudon. The thing is, it was nerfed instantly when Torkoal also gained Drought in Generation VII as Torkoal had a more focused stat-spread and a nice pool of utility moves to go along with setting the sun. Ninetales, by comparison, has subpar stats and nothing more than standard Fire-type attacks.
3 Generation III: Torkoal
Speaking of which, the volcanic tortoise of Hoenn has his role in competitive battling locked up for the time being. To elaborate on Torkoal's takeover as the premier sun-setter in the current metagame, one need only look at its accessibility to a wide array of utility moves.
Even more so than Ninetales prior to Generation VII, it naturally works great as a lead. Alongside the sun, it can place Stealth Rocks, take away opponents' hazards with Rapid Spin, or Yawn or Toxic away an opponent's lead. Better still: it does all of this while having an excellent 140 Defense and moves such as Overheat, Lava Plume, or sun-boosted Weather Ball as great STAB options.
2 Generation II: Entei
Entei's second-place standing on this list isn't much to be honest. Despite its Legendary status and expectedly high base stat total, Entei has had a surprisingly hard time breaking through to levels of true competitive viability. That largely has to do with its spread of said 580 base stat total.
It has great Attack at 115 and is at least OK in most areas, but its Speed, while at an acceptable level of 100, could be better for a Legendary Pokemon. After all, Entei doesn't have any truly distinctive qualities and bears the lackluster abilities Inner Focus or Pressure. Its movepool isn't spectacular either, but gaining Sacred Fire in Generation VI has made it more viable recently as a solid all-around presence.
1 Generation VIII: Cinderace
Take note: the gap between first and second place on this list is huge. Galar's Fire-type starter has played what was essentially Greninja's role as a multi-typed chameleon to a tee. It has dominated the current metagame as a result.
With the help of its hidden ability, Libero, Cinderace takes on the type of whatever move it uses -- basically making all its attacks STAB. Said movepool is incredibly wide containing signatures such as Pyro Ball and Court Change and coverage such as High Jump Kick, U-Turn, and Gunk Shot. Of course, this takes care of its supposed burden as a single-typed Pokemon which works great in conjunction with its excellent Attack and Speed.
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