Curse Hitmontop is pretty awesome
Just wanted to write a post about a Pokemon I think has a lot of potential, Curse RestTalk Hitmontop. I would like to take credit for this set but that honor in reality goes to
zben, I just happened to "discover" it separately (convergent evolution or something).
The Set

Hitmontop @ Leftovers
Ability: No Ability
- Curse
- High Jump Kick
- Rest
- Sleep Talk
What's It Do?
Curse Hitmontop is a potentially extremely dangerous setup sweeper that doubles as an effective answer to opposing Curse Normal types. Curse Hitmontop is additionally extremely bulky, having enough Special Defense to not be 3HKOed by Octillery (like Hitmonlee and Hitmonchan), and it has a solid 95 Defense and Curse for the physical side.
Weezing and Pineco may be able to switch into it relatively freely, just like against Primeape and Hitmonlee, but by no means are they seriously threatening Hitmontop. Hitmontop can get two Curses off before Pineco gets to use a move, and Explosion will bounce off, only doing a maximum of 55, and from there Hitmontop can Rest the damage off. Weezing is faster than -1 Hitmontop, but the only move it can actually use to seriously threaten it is Explosion, though it has to be immediate as otherwise Hitmontop will Curse again and Explosion will not be nearly as threatening. Weezing does have access to Haze and Curse, but it only uses these occasionally, and most common sets (Explosion + coverage move) will lose to Hitmontop very quickly.
Hitmontop's primary defensive niche is answering Curse Normals. Hitmontop can pretty easily switch into Wigglytuff or Porygon quite easily with its huge Defense and threaten them out with Curse and Fighting STAB. Even if Hitmontop is paralyzed prior, Wigglytuff and Porygon still have to bank on full paralysis, as otherwise Hitmontop will Curse up and then heal itself. Hitmontop may also be able to gain entry on a Wigglytuff Rest or Porygon Recover before they use Curse, and a Porygon paralyzing Hitmontop on the switch-in with Thunder Wave still has to run away. And, of course, Hitmontop can get plenty of chances to Rest off paralysis with its large bulk, especially against bulkier balances. Hitmontop has additional defensive utility, namely being able to switch into Dewgong and, if needed, Stantler and Octillery, though the latter two are much more inconsistent considering how much harder Stantler hits and Hitmontop sometimes lowering its Speed through Curse while using Sleep Talk when facing Octillery. For checking these three Pokemon specifically though, I find it much better to have Hitmontop as a backup or secondary option than crutching on it, especially against Stantler.
Hitmontop is difficult to answer defensively. Again, Hitmontop isn't 3HKOed by Octillery's Surf, and that's one of the strongest special attacks in the entire tier. Magmar, Flareon, and Rapidash can 3HKO Hitmontop with Fire Blast, but all of them are 2HKOed by +1 High Jump Kick and they have to simultaneously contend with Fire Blast accuracy and PP, Hitmontop being able to call Rest with Sleep Talk, and in the case of Dash and Flare, often being asleep due to their own defensive duties. On the physical side, nothing can really touch Hitmontop (asides from immediate Explosions) once it has Curse boosts up, and even before using Curse it's still quite bulky. Fearow can only do a max of 43.5% with Drill Peck even with only one Curse boost from Hitmontop, and then Hitmontop can boost to +2 and Drill Peck isn't even a 3HKO and it heals back to full with Rest and it's a wash.
There are only a few reliable ways to answer Hitmontop. Xatu, Exeggcute, Gastly, and Curse/Haze Weezing. Xatu obviously is a big nuisance, not just completely blanking Hitmontop but threatening it severely and just being a dangerous special attcker to give repeated free turns to. There aren't many ways to forcibly remove Xatu either; you have to use Houndour which is really not very good, or you can try and Explosion trade with it using Weezing or Pineco, or you give up on trying to clear Xatu out of the way and relegate Hitmontop to being useful in non-Xatu matchups and maybe doing something against Xatu teams if you manage to kill it mid-game. Exeggcute, while it doesn't have a 4x Fighting resist, still has solid Defense and is plenty capable of taking on Hitmontop, especially since it still does resist it and an unboosted High Jump Kick is so weak relative to other physical STABs. Hitmontop also has to run immediately which gives Exeggcute additional Leftovers. Gastly of course can't even be hit by High Jump Kick, and once the opponent knows you have Hitmontop they will probably not throw away Gastly willy-nilly. Haze and Curse Weezing can both effectively cancel out Hitmontop's Curse boosts and then use Explosion on it. In the case of Weezing being RestTalk rather than Explosion, it can fish for crits, and if that doesn't go well due to Sludge Bomb's limited 16 PP, then Weezing should still be able to PP stall Hitmontop. However, asides from Xatu, Hitmontop's counterplay is generally very specific and uncommon.
What Some Curse Hitmontop Teams May Look Like
(Note: The first four teams are all my teams [hence the nicknames], though I did build them with the help of
MrSoup)
Pory Lead Stantler
https://pokepast.es/a72a302860c0ae3c
Tales Lead Stantler
https://pokepast.es/81b77398cf4ea80d
Fearow Lead Porygon
https://pokepast.es/b490dd4c7acc5366
Fearow Lead Ninetales
https://pokepast.es/c87e06a6d8082814
All four of these start off with one simple structure - Hitmontop of course, and then Gloom, Graveler, and Dewgong. Dewgong is the resident primary Xatu check, and it also covers threats like Rapidash, Flareon, Reflect Ninetales, Gloom, Dugtrio, Graveler, and Pupitar. Dewgong is also quite fast and can freeze things. Gloom is the long-term Primeape check. The other option is RestTalk Weezing (since I don't think Explosion Weezing is the right call for such an intentionally bulky and slower team), but I chose Gloom for its Octillery-checking capabilities. Gloom is also not threatened by Grounds. Ultimately, I chose Stun Spore + Curse on Gloom for Stantler and for paralyzing things, especially Weezing, Xatu, and Pineco, but if you want a Gloom potentially more directly able to trade with Xatu or a Gloom not walled by Magnemite and Weezing, you could throw on moves like Swords Dance or Hidden Power Ground. Graveler at this point felt pretty mandatory since I have two Pokemon that both let in Pineco nearly for free, are threatened by Fearow, and don't prefer [Fire Blast] Weezing's company.
From there, I had a few options for the final two slots: Stantler, Ninetales, Fearow, and Porygon. Since I couldn't choose which I wanted to pick, I just made a version with each combination except for Fearow/Stantler and Ninetales/Porygon. The reason I didn't make one with Fearow/Stantler is because neither are consistent Xatu switch-ins and that left me with Dewgong as my only switch, which is very easy to exploit, and I didn't make one with Ninetales/Porygon because the team felt slow, but this one is probably fine.
Fearow - speed control, strong offensive threat, good lead to threaten Stantler/Pineco/Xatu/Flareon, pretty good against Persian lead, helps against Stantler, Dugtrio, and Xatu
Ninetales - Great answer to Hitmontop's answers, shuts down Magmar and can PP stall opposing Sunny Tales, Reflect for Stantler (and using Sunny would be griefing Flare/Dash matchup), speed control (kinda), helps a lot vs Magnemite, very difficult to kill
Porygon - Positive Xatu and Stantler matchups, difficult to kill, can paralyze Pineco and Primeape, strong alternative win condition regardless of if Hitmontop is able to be useful in a given game, reliable Dewgong switch-in (can hide Hitmontop for the late-game)
Stantler - Strong offensive threat, speed control-ish, helps a lot vs Weezing, reliable Dewgong switch-in, decent alternative Chinchou switch-in if you don't want to risk Gloom being paralyzed, help vs Magnemite, can force damage on or even eliminate Pineco.
Notable weaknesses for these teams include Kingler, Sunny Day Ninetales/Magmar for the two without Ninetales, Growth Pass Flareon, Pupitar (except for Ninetales/Stantler), Pineco (to a degree), and funny enough even Hitmonlee (Gloom does not like taking repeated Body Slams). However, I think they are all still very good teams and some of the teams I'm most proud to have made.
CurseTalk Weezing Tentacool (by zben)
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https://pokepast.es/73a6c0d2aa706e09
I can't really speak as to the true intentions of the team since I didn't build it but I can do my best. The combination of Curse Talk Weezing and Curse Hitmontop is incredibly potent into teams without Xatu, and Weezing of course serves as a wall for Primeape and Hitmonlee. In the matchup against Xatu, Porygon can do great work, and Tentacool can permanently keep off Spikes to make taking Xatu's hits easier. Encore Dewgong can allow for good positioning with regards to forcing the opponent to lock into an easily resistable move or locking a Pokemon into Rest, and it shuts down Baton Pass and can potentially prevent Curse sweeps in precarious scenarios. Encore also has the benefit of wasting Pokemon's PP even if it may not necessarily be needed for another situation at the moment, further reinforced by its ability to be called by Sleep Talk.
Zben told me the last slot is intechangeable. He said Tangela is here for answering Kingler, Sudowoodo, and Grounds, and it can also paralyze Fire types which are a serious threat to the team. I asked what he would use if he didn't use Tangela in the last, and he said Stantler or Wigglytuff, which makes sense seeing as they benefit from Tentacool hugely and are their own dangerous offensive threats with defensive utility. Stantler additionally provides some speed control, which is otherwise sorely lacking. All three of Tangela, Stantler, and Wigglytuff are also Chinchou checks, which is important especially if you don't want to reveal Hitmontop early.
Porygon Lead Tentacool Explosion Weezing (by MrSoup)
I don't have the pokepaste so I don't know the last Pokemon (it's probably Dewgong), but I would still like to highlight this team. This team takes a very similar angle to Zben's team with the Tentacool, but with a much more outwardly offensive angle, as seen with Explosion Weezing and Fearow. The main goal of the team seems to be to overwhelm Xatu offenses by controlling them through hazard removal and hitting them right away with huge threats like Porygon (which is even leading), offensive Weezing, and Fearow. Meanwhile, against slower and bulkier teams where Fearow and Weezing may not have as much steam and Porygon might have more trouble (though it's still definitely potent in these matchups), Curse Hitmontop can take over and just chill and threaten to win the game since there will most likely not be a Xatu on fat spikeless.
Overall, Curse Hitmontop does have some issues since it arguably demands the entire rest of the team be built around it and it's close to dead weight against teams with one of the most common Pokemon in the whole tier, it's incredibly dangerous in matchups where it's not facing Xatu, and Xatu is less common (though definitely not uncommon) than ever and may continue to decline, and I definitely think it deserves recognition. I honestly think Curse Hitmontop is good enough to bring Hitmontop from an otherwise B- Pokemon stuck on stall to a genuine B or B+ threat at minimum.