
https://www.smogon.com/dex/rs/pokemon/koffing/
[Overview]
Koffing is probably the most complete counter to Hitmonchan in NU. I'll let that sink in for a moment. Sableye comes close to holding this title (it actually does with RestTalk but that's a poor use of Sableye), but Koffing is also unaffected by Toxic and Spikes and has access to Will-O-Wisp, letting it beat all forms of the punching menace. Outside of that specific role, Sableye is probably a better fit for your team as it has an easier time countering other dangerous Choice Band users such as Pidgeot and Raticate. But if you absolutely need the best possible answer to Hitmonchan and want burns spread around your opponent's team, then Koffing may warrant closer consideration.
[SET]
name: Physically Defensive
move 1: Will-O-Wisp
move 2: Sludge Bomb
move 3: Pain Split
move 4: Explosion / Haze
item: Leftovers
ability: Levitate
nature: Impish
evs: 252 HP / 4 Atk / 252 Def
[SET COMMENTS]
- Get in on Hitmonchan and click Will-O-Wisp, just be sure to not burn something like Raticate
- Sludge Bomb is a decently strong STAB move and lets Koffing enjoy its ability to take on Grass-types as well
- Pain Split can really mess with Wailord and is Koffing's most solid method of healing
- Explosion allows Koffing to take out a specific threat if needed
- Haze can be used instead to prevent things from using it as setup bait
[ADDITIONAL SET COMMENTS]
- Max Defense needed to make use of the fact that Koffing counters Hitmonchan even without a burn
- Works well on balanced teams as the burns it spreads and Explosion can open up setup opportunities for teammates
- Best teammates are those that need a solid answer to Hitmonchan, particularly Normal- and Rock-types like Kecleon, Graveler, and Relicanth
- Also appreciates teammates to switch into Chimecho and other special attackers, Dewgong, Roselia, and Flareon
[Other Options]
- Destiny Bond
- Fire Blast
- Memento
- Screech, Torment, Thief, Toxic
[Checks and Counters]
- Bulky Water-types
- [Inset Special attacker here] Haunter, Chimecho, Flareon, Huntail, Pikachu
- Torkoal
- Swalot
- Raticate