Level 100 Statistics (see level 5, 50, 100)
In a tier filled with many viable Fighting-type Pokemon, Hitmonchan struggles to stand out. Hitmonchan often finds itself weaker, slower, or frailer than other Fighting-types, and in some cases all three. It is also flawed as a Rapid Spin user, as it cannot handle spinblockers very well unlike the usually superior option, Kabutops. Hitmonchan also doesn't have any tricks up its sleeve to get past Psychic- and Ghost-types like some other Fighting-types; with these things in mind, it might seem like Hitmonchan has nothing going for it.
Despite generally lacking in stats, and to an extent in movepool, Hitmonchan does have a small niche provided by Iron Fist. It has access to a very wide array of punching moves, including the rare Mach Punch and the elemental punches, a trait only shared by Gurdurr. Due to this, its coverage moves hit harder than its competition, and Mach Punch, a move most other Fighting-types lack, can revenge kill a large number of threats, especially those that are weak to it. Overall, always consider your other options before using Hitmonchan, but don't discount it completely, as it might be just what you are looking for.
A simple offensive set is the best way to utilize Hitmonchan. Although it might not look very unique at first, access to Iron Fist, a plethora of punching moves that get boosted by said ability, and priority in Mach Punch give it all the advantages that it needs and somewhat make up for its inferior power. Without Psychic- and Ghost-types, Hitmonchan is surprisingly difficult to wall, so it can serve as an effective wallbreaker with its good coverage while keeping faster Pokemon in check with Mach Punch. Drain Punch is the preferred STAB option, as it gets boosted by Iron Fist, making it reach decent levels of power while simultaneously healing off damage taken from Life Orb. Alternatively, Close Combat can be used, as even factoring in Iron Fist it is stronger than Drain Punch. Mach Punch is an important move for Hitmonchan, as it is one of the few Pokemon that can learn the move, allowing it to finish off or revenge kill foes weak to it; for example, it almost always OHKOes Sawsbuck and Crawdaunt after Stealth Rock damage. ThunderPunch allows Hitmonchan to 2HKO bulky Water-types, such as Poliwrath and Slowking, and it can also hit Flying-types hard on the switch. Ice Punch is preferred for the final slot, getting good coverage with ThunderPunch to form a pseudo BoltBeam combination and hitting Pokemon such as Tangrowth, Druddigon, and Amoonguss for super effective damage. However, Hitmonchan could instead use Rapid Spin in this slot, as it allows Hitmonchan to rid the field of hazards, though this is at the expense of losing coverage. Keep in mind though that it loses to all relevant spinblockers, so only use it in case space cannot be made on your team for the few other Rapid Spin users in the tier and Hitmonchan's other traits are needed.
Team Options & Additional Comments >>>
Most of what Hitmonchan has access to is used better by something else. Hitmonchan can run a set with Rapid Spin and Foresight, guaranteeing a spin. However, such a set has numerous problems: Hitmonchan has four-moveslot syndrome, lacks good resistances, has a mediocre physical bulk even when invested, does poorly against Ghost-types already, and most Ghost-types are unable to defeat Kabutops, another Rapid Spin user. Hitmonchan learns Agility, which can allow it to sweep late-game, but Hitmonlee has a much easier time doubling its Speed thanks to Unburden, which allows it to attack and set up in the same turn. SubPunch is an interesting option on Hitmonchan, considering Focus Punch is boosted via Iron Fist, raising the power of the move to near-unmatched levels, but there are not very many cases where Hitmonchan will be able to keep the Substitute up, and it doesn't beat any additional Pokemon with Focus Punch. Bulk Up is mostly outclassed by Gallade due to higher stats in almost every area; although Mach Punch gives Hitmonchan a slight advantage, it is not enough to make it worth using over Gallade. Stone Edge can nail Flying-types a bit harder than ThunderPunch while also hitting Fire-types hard, but Hitmonchan already either easily defeats or flat-out loses to all of the Flying-types in RU, and Stone Edge does not alleviate this fact. Hi Jump Kick is stronger than even Close Combat, but the side effect is very undesirable, and it isn't that much more powerful. Finally, Hitmonchan has access to Bullet Punch and Fake Out, but Bullet Punch has redundant coverage with Mach Punch, and Fake Out can become a waste of space considering that its damage output is fairly low.
Checks and Counters
Just like other Fighting-types, Hitmonchan struggles against Ghost-type Pokemon such as Misdreavus and Rotom, which are immune to Hitmonchan's Fighting moves, can burn it with Will-O-Wisp, and then proceed to wear it down with repeated Shadow Balls. Psychic-types, such as Uxie or Mesprit, are similar cases, since even though they are not immune to Fighting-moves, they still do not take very much damage from them and can hit Hitmonchan hard with their STAB. Flying-types, such as Sigilyph, Moltres, and Scyther, can outspeed and OHKO Hitmonchan with their super effective STAB moves and switch into Fighting moves with ease, but they must watch out for ThunderPunch and Ice Punch. Durant and Galvantula are not weak to anything Hitmonchan commonly carries and can deal a lot of damage with Thunder and Iron Head, respectively, though both must watch out for the rare Fire Punch. Finally, in a general sense, Hitmonchan's stats can work against it in one-on-one situations. Generally, if the foe is a strong physical attacker, is not weak to Mach Punch, and is faster than Hitmonchan, there is a very good chance that the Pokemon can do massive damage to if not OHKO Hitmonchan, with examples including Entei, Gallade, and Choice Scarf Emboar.