I'd like to nominate
Mandibuzz
from
UR to C+
Although I profoundly believe B tier more accurately represents its viability, C tier appears to be where the
miscellaneous stall niche dump resides.
I've been testing variants of Mandibuzz stall since last year, and I'm honestly surprised with how criminally under explored the benefits of Mandibuzz are to the stall archetype. This is not just the Omari P meme bird; it's amalgamatory and compressing of several key defenisve roles that stall teams deseperately need, in this meta particularly.
Major advantages of Mandibuzz stall:
- 1A: Walls
Band Zygarde. No other defogger even comes close to this. Band Zygarde also 2hko all unawares + Max Def Tangrowth
- 2A: Walls and threatens
Mega Charizard-X, a notable stall threat that decimates quagsire and pyuk based stalls through Outrage. If clefable is your unaware wall then you're pretty much fucked no matter what. I.E,
every unaware user is threatened by Charzard-X in some way or another, therefore a defogger that easily man handles it while managing other stall threats is phenomenal.
-3A: Threatens A-Marowak. A-Marowak is infamously annoying to stall as frequent defense drops via Shadow Bone turns 3hkos on Unawares into easy 2hhkos. Since Quagsire and Pyuk have to first switch in, and then recover spam up on A-Marowak it is very easy for alola wak inflict a crippling defense drop eventually. As your bird on Stall tends to be your secondary physical defense pivot there exists inherent openings for alola wak to threaten the rest of your stall team as no other defensive bird/ground immune defogger can handle it reliably.
Mandibuzz outspeeds alola wak therefore negating setup opportunities, and if you've elected to use Big Pecks as its ability then it's even more certain to wall its attacks.
-4A:
Walls Adamant Choice Band Hoopa-U. This is the crowning benefit of Mandibuzz Stall. CB Hoopa is incredibly under-prepared for on Stall with answers to it being incredibly niche or haphazard to the cohesiveness of the overall stall build. If you're lucky enough with FB misses then it can even handle hoopa's specs variant with ease, or at the very least, increase prediction stress on the specs Hoopa user (between choosing Sab, Chans, and Madi etc.). Mandibuzz similarly pressures a specs lele user's prediction. Protect Mandbiuzz helps achieve this with a secondary benefit to soak incoming boosted physical z-damage. I have other prepared answers on stall for Hoopa but I'd rather keep those to myself
-5A: Soft (sometimes hard) checks Blacephelon. Blace is another "anti-stall" pick, yet Mandibuzz walls and ohkos unboosted Blace with ease. A blace user is unlikely to pivot it in on Mandibuzz defogging, unlike all other defoggers it favours to. Mandibuzz laughs off even boosted Z-shadow ball from Blace.
-6A: Can check Band Crawdaunt, especially if knock off is carried on Mandibuzz or is used earlier by another member of your team.
-7A: Overcoat allows it retain its leftovers healing in hazardous weathers, unlike Zapdos. You wll very rarely see spore or stun spore, but overcoat is helpful even in those circumstances. It's other useful ability, Big Pecks, helps it to wall attacks that other defoggers or unawares struggle with, such as shadow bone and liquidation/crabhammer.
Other random stuff: A mixed or SpD spread walls specs normal greninja and can defog on it; Iron Defense variants with Rocky Helm can wall and eventually straight out OHKO m-mawile through foul play and helm recoil -- unlike Iron Defense Skarm which fears a magnet trapper paired with Mawile. Z-Ground lures in and trashes incoming Heatran and Mawile.
mods: I have to go rn but I'll post calcs and replays later tonight, just wanted the bulk explanation out of the way first.
Replays (had to dig since I don't like showing new teams):
https://replay.pokemonshowdown.com/gen7ou-738742579 Hoopa-U
https://replay.pokemonshowdown.com/gen7ou-740845367 Screens Zygarde
I love Mandibuzz but I disagree with it being C+ and before I give my opinion of where it should be placed, let me just reply to your key points.
You say no other defogger comes close to walling Band Zygarde, but there are actually others like Mega Scizor and Phy Def Gliscor which also can defog and avoid the 2HKO from any of its attacks and I'll post these calcs below. They have also have additional benefits such as Gliscor being able to set its own rocks and being status immune.
252+ Atk Choice Band Zygarde Outrage vs. 252 HP / 252+ Def Mandibuzz: 187-222 (44.1 - 52.3%) -- guaranteed 3HKO after Leftovers recovery
252+ Atk Choice Band Zygarde Thousand Arrows vs. 248 HP / 252+ Def Scizor-Mega: 115-136 (33.5 - 39.6%) -- guaranteed 3HKO
252+ Atk Choice Band Zygarde Outrage vs. 252 HP / 252+ Def Gliscor: 166-196 (46.8 - 55.3%) -- guaranteed 3HKO after Poison Heal
There are also bulky pokemon like Slowbro that are getting more common which can deal with Band Zygarde even if it spams Outrage.
252+ Atk Choice Band Zygarde Outrage vs. 252 HP / 252+ Def Slowbro: 181-214 (45.9 - 54.3%) -- 5.9% chance to 2HKO after Leftovers recovery
Outrage on ZardX is a move that is basically non-existent on high ladder, and due to prevalence of fairies and steels in this meta, locking yourself into Outrage isn't a good situation when there are other moves such as Dragon Claw being available options. Even then, Mandibuzz doesn't even wall Outrage ZardX as at +1 it easily 2HKOs Mandibuzz and Foul Play doesn't OHKO in return, so assuming you switched Mandibuzz into ZardX and it clicks DD, then it would still drop like the unaware walls.
Alowak is annoying for sure for stall and Mandibuzz can deal with it assuming it runs Knock Off over Foul Play, but even then Mandibuzz can't deal with Alowak when TR is up as it is 2HKO'd almost every time and stall usually doesn't have a way to stop TR from going up due to most teams not running taunt or having the power to quickly break through the setters.
252+ Atk Thick Club Marowak-Alola Flare Blitz vs. 252 HP / 252+ Def Mandibuzz: 216-255 (50.9 - 60.1%) -- 87.5% chance to 2HKO after Leftovers recovery
Now Mandibuzz is able to wall Band Hoopa-U and is the main reason that I ever consider using Mandibuzz on my teams as Hoopa-U is one of stalls biggest concerns and is getting increasingly common. But moving it onto the VR for that reason alone would be the same as putting a mon like Arcanine there simply because it deals with Mega Mawile with Intimidate and Will-O-Wisp which is another mon that is getting more common. Pokemon like Maggron which have made their way onto the VR can do other things outside of dealing with one huge threat.
Assuming Mandibuzz manages to switch into Blace for free, then yes it can check Blace but if Blace does even one CM it becomes increasingly risking for the Mandibuzz as Z-Fire Blast will easily OHKO and lets be honest, most of the time Mandibuzz isn't getting in on Blace without taking damage unless Blace does Sub, and then it can CM after while you waste a turn breaking it.
Mandibuzz does not actually deal with Banded Crawdaunt at all. Band Crawdaunt if not on TR runs Speed, easily enough to outpace Mandibuzz meaning that unless you run 136speed to speed creep it and miss out important benchmarks that your earlier points made such as Band Zygarde, you can't even Knock Off Crawdaunt in time to live the second Crabhammer.
252 Atk Choice Band Adaptability Crawdaunt Crabhammer vs. 252 HP / 252+ Def Mandibuzz: 214-254 (50.4 - 59.9%) -- 85.9% chance to 2HKO after Leftovers recovery
And like with Alowak, if its in TR then Mandibuzz can deal with it outside of TR but not inside of it, so its still an unreliable option to have as your Crawdaunt switch.
You wouldn't really use a Mixed or Spd Spread because other mons just do the job better. If you really wanted to wall Ash Greninja you could simply opt for Mantine for example. Iron Defense Mandibuzz could deal with Mawile in theory but it can't do what Shed Shell Skarm can and switch into anything Mawile can do before using Iron Defense. There's no point making an option for it deal with pokemon if it can't switch into them in the first place on stall. Z-Tectonic Rage sounded nice, and it does hit Heatran hard, it still fails to OHKO even without any investment on Heatran and does a pitiful amount to Mawile, so lefties would be better in almost every situation for the passive recovery.
0 Atk Mandibuzz Tectonic Rage (140 BP) vs. 40 HP / 0 Def Mawile-Mega: 118-140 (47 - 55.7%) -- 73.8% chance to 2HKO
I feel this meta is not kind to Mandibuzz at this time. Fairies and run Steels run rampant and Mandibuzz struggles to deal with them. Even with Kartana, Z-Giga is growing in popularity due to being able to OHKO Zapdos and the same applies to Mandibuzz.
+2 252 Atk Kartana Breakneck Blitz (200 BP) vs. 252 HP / 252+ Def Mandibuzz: 389-458 (91.7 - 108%) -- 50% chance to OHKO after Leftovers recovery
Mandibuzz also suffers from the fact that it can't deal with basically any of the common hazard setters. Unlike pokemon like Mantine which can switch into Ash Greninja, Skarm for Landot or Zapdos for Ferrothorn, Mandibuzz isn't able to switch into any common pokemon which can set up hazards which makes its a bad choice to have as a defogger as all common setters have at least one set that can beat Mandibuzz such as Suicide Lead Landot, Z-Outage Garchomp. This means that even if Mandibuzz switches in, then pokemon like Toxapex or Ferrothorn that can't do much damage, can still constantly lay down hazards until Mandibuzz switches out because of Leech Seed/Toxic.
Mandibuzz may have a small niche in this meta currently to be maybe C-, but I feel its better off left UR due to the reasons I stated.