At first glance, one may simply dismiss Medicham, with its poor base stats and ridiculous appearance. But, it would seem, pink pantaloons are not merely a source of ridicule, but also the source of Pure Power. Taking its ability into account, Medicham has the highest Attack stat in the game, with the exception of Deoxys-A, letting it pack a mean punch. This is backed up by a workable base 80 Speed, which allows Medicham to outrun the unboosted metagame with a Choice Scarf, and pretty much all defensive Pokemon without. On top of this, Medicham has access to Hi Jump Kick, a stupidly powerful move; Medicham's Hi Jump Kick is the second most powerful non-suicidal move you're likely to see, trumped only by Darmanitan's Flare Blitz.
The less that is said about Medicham's defenses, though, the better. Medicham is not quite in Dugtrio or Sharpedo territory—it can take a Choice Band Scizor Bullet Punch, but this is not exactly an achievement. Getting Medicham safely into battle may be a challenge. Another major concern for Medicham is competition from other Fighting-types such as Mienshao and Terrakion; both possess significantly better stats, excluding Attack. Notably, Medicham has access to Psychic STAB; though neither Zen Headbutt nor Psycho Cut has good Base Power, both are reliable and hit Pokemon such as Tentacruel hard. Without these moves, Medicham is extremely vulnerable to Ghosts and the move Protect, each of which will cause 50% recoil when using Hi Jump Kick. At least Medicham has a secondary STAB. More importantly, Medicham has access to Ice Punch, ThunderPunch and Trick, letting it take out Gliscor easily and cripple defensive Pokemon. Overall, this means that Medicham has very few, if any, safe switch-ins. Make sure not to underestimate the power of Hi Jump Kick.
Given Medicham's already outrageous power and average Speed, a Choice Scarf set seems entirely obvious, letting Medicham outrun the vast majority of Pokemon in the OU metagame. However, Medicham achieves more than your typical Choice Scarf user; it can not only play a revenge killing role, but also break through most walls, and even sweep late in the game under the right conditions. Largely, this is due to the sheer power of Hi Jump Kick; a 130 Base Power move coming from an effective base Attack stat of 169 is no laughing matter. For example, Adamant Medicham can 2HKO Skarmory and OHKO 112/0 Rotom-W. Hi Jump Kick is almost as powerful as a super effective Psycho Cut, so you'll want to be spamming it as soon as it is safe to do so. Unfortunately, Ghost-types and the move Protect will both cause Medicham to receive 50% recoil, so another STAB attack can often prove useful. In this regard, Psycho Cut and Zen Headbutt are great options; they might have low Base Power, but they provide a less risky move for revenge killing weakened threats, and hit Poison-types, such as Gengar and Tentacruel, super effectively. The choice between the two is a little tricky; Psycho Cut is generally preferred as this set uses its Psychic STAB to reliably kill weakened opponents. Zen Headbutt's chance to miss is not appreciated, leaving only Ice Punch as an accurate move, but it is significantly more powerful than a resisted Hi Jump Kick, and has a very handy flinch chance.
Ice Punch is Medicham's main coverage move, as it deals super effective damage to a number of Pokemon that resist Hi Jump Kick; it OHKOes Dragonite and Latios after Stealth Rock damage, and easily 2HKOes Gliscor. Trick provides a very good option for the last slot, differentiating Medicham from other Fighting-types by allowing it to cripple the likes of Jellicent, Reuniclus, Mew, and Slowbro. Also, if the Choice Scarf is proving inconvenient (for example, if the opponent has a Ghost-type or is spamming Protect) it can be removed. ThunderPunch allows Medicham to 2HKO Jellicent and OHKO Gyarados, but will fall short of a 2HKO on Slowbro.Team Options & Additional Comments >>>
Though it might be tempting to equip Medicham with a choice item, the power and flexibility provided by other items can be extremely useful. Instead of a revenge killer, Medicham becomes a potent wallbreaker and destroyer of defensive teams. Medicham also becomes much less vulnerable to Ghosts, Gliscor and Protect. In fact, if played correctly, Medicham can actually take advantage of Protect by using Substitute, which can ease prediction in addition to blocking status moves. However, the damage from Substitute, Life Orb and potentially Hi Jump Kick recoil will build up tremendously fast, so you might wish to consider another option. Drain Punch provides a reliable STAB move with a useful secondary effect, preventing Medicham from being worn down. This is an excellent move to use against opponents which spam Protect, and is good for finishing off weakened Pokemon. Black Belt is a viable alternative item, providing a boost to Hi Jump Kick comparable to that of Life Orb without causing recoil. This also lets Medicham convincingly bluff a choice item before surprising the opponent. Ice Punch is a required move, giving a good chance to OHKO 252/184+ Gliscor, and guaranteed OHKOs on 4/0 Salamence and Latios, as well as Dragonite after Stealth Rock damage. Zen Headbutt or Psycho Cut gives Medicham a reliable STAB attack that also hits Tentacruel, Gengar, Fighting-types, and Jellicent harder than the other moves. Psycho Cut is noticeably weaker and doesn't cause flinches, but also doesn’t miss. Still, a miss is not the end of the world when behind the safety of a Substitute, so Zen Headbutt may be the better option in that case.
Overall, this set is extremely potent, but it does have a tendency to fall flat on its face occasionally. It's not the most consistent Pokemon ever. Medicham will often prove useful against more defensive players, especially those that underestimate its power. Offensive teams, on the other hand, can present trouble; nonetheless, Medicham should be able to attain a KO every time it gets in safely. Another issue worth bearing in mind is that an intelligent opponent can often wear Medicham down with smart switches, especially if they have a Ghost. Therefore, Medicham requires much more prediction than your typical Substitute user especially if running Life Orb. You should also think carefully as to whether the much weaker Mienshao might make a better choice thanks to better Speed and Regenerator, which gives it much better longevity. Still, rest assured that almost nothing can match Medicham's sheer power.Team Options & Additional Comments >>>
As far as alternative sets go, the most obvious is Choice Band. This is a lot less flexible than the non-choice set, leaving the opponent able to sacrifice something before forcing Medicham back out; the extra attack is often just overkill. Still, the set would be Hi Jump Kick, Ice Punch, and two of Drain Punch, ThunderPunch and Bullet Punch. A number of other moves could occasionally prove useful: Double Edge hits Psychic-types harder than any of Medicham's other moves, but this is a bad move to be locked into, and the recoil is not appreciated when running Life Orb. Fire Punch allows Medicham to OHKO Scizor and Forretress (assuming Sturdy is broken), but these Pokemon are already taking a ton from Hi Jump Kick. Rock Slide is useful against Volcarona and Flying-types, but a Psychic-type move or Ice Punch is more effective in general. Foresight allows Medicham to hit Ghosts with Hi Jump Kick, but you can KO most in the required two turns anyway. Pain Split can be used on a set with Life Orb an Substitute to provide longevity and damage opponents, but Medicham's coverage is sacrificed. Acupressure or Bulk Up can be used to set up on opponents that spam Protect, but Medicham's average Speed leaves it too vulnerable to revenge killing.
Checks and Counters
Directly countering Medicham can prove extremely difficult, due to its phenomenal power and decent coverage. However, there are still a couple of ways to deal with Medicham effectively. First and foremost, we have Ghost-types; the mere presence of a Ghost will hamper Medicham significantly, preventing it from using Hi Jump Kick freely. However, most Ghosts are not themselves perfect counters; Gengar is OHKOed by a Psychic-type move or a Choice Band Ice Punch, Jellicent falls to ThunderPunch or a Life Orb Zen Headbutt, and many other defensive ghosts, such as Sableye, Dusclops, and Cofagrigus, absolutely hate Trick. Psychic-types cannot hinder Medicham purely by existing, but are often great switch-ins. Slowbro, Stallbreaker Mew, and Calm Mind Reuniclus can usually counter Medicham if they avoid Trick. Gyarados can also wall any variant lacking ThunderPunch. Moreover, several Pokemon are not 2HKOed by Choice Scarf Hi Jump Kick, including Dragonite, bulky Volcarona, Gliscor, Celebi, and Intimidate Salamence. Finally the move Protect is also an effective check to Medicham, as it punishes Medicham for using Hi Jump Kick. This is very effective against the Choice set, but less so against other sets as they can take advantage of the free turn, for example with Substitute.