Against non stall teams, I think Throat Spray Clangorous Soul Kommo is actually super slept on right now. It dismantles offense and even balance builds that rely on clefable to handle standard defensive kommo, since it just gets blown away by plus 2 flash cannon after some chip. Toxapex is definitely an issue for it, but if you take care of toxapex then it really just rips through anything not name Blissey. It also sets up really easily on common mons like Crawdaunt, mandibuzz, zeraora, urshifu. It only really fits on hyper offense, but it is a great check to other hyper offense mons as well as a sweeper itself. It's kinda cheesey, but is a pretty underrated set atm in my opinion.
Kommo-o @ Throat Spray
Ability: Bulletproof
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
IVs: 0 Atk
- Clangorous Soul
- Clanging Scales
- Flamethrower
- Flash Cannon
While flamethrower lets you shred things Corviknight and Ferrothorn easier, I think a mixed set with Close Combat could end up more effective to potentially lure and shred Blissey. There's pros and cons, but here's some calcs.
Kommo-o @ Throat Spray
Ability: Bulletproof
EVs: 252 Atk / 40 SpA / 216 Spe
Naive Nature
- Clangorous Soul
- Clanging Scales
- Flash Cannon
- Close Combat
216 speed helps avoid getting flinched by togekiss pre-boost and scarf togekiss post-boost. Naive nature because most of the things that Kommo-o sets up on are physical, as are most priority moves. Max attack is basically there as a proof of concept, you could play around with the balance between the two if you feel like it.
Blissey dies very hard:
+1 252 Atk Kommo-o Close Combat vs. 200 HP / 252+ Def Blissey: 948-1116 (135.2 - 159.2%) -- guaranteed OHKO
A lot of the things covered by flamethrower still don't appreciate +1 CC or +2 Clanging Scales:
+1 252 Atk Kommo-o Close Combat vs. 248 HP / 8 Def Scizor: 259-306 (75.5 - 89.2%) -- guaranteed 2HKO after Leftovers recovery
+1 252 Atk Kommo-o Close Combat vs. 252 HP / 252+ Def Ferrothorn: 312-368 (88.6 - 104.5%) -- 68.8% chance to OHKO after Stealth Rock
+1 252 Atk Kommo-o Close Combat vs. 0 HP / 0 Def Excadrill: 788-930 (218.2 - 257.6%) -- guaranteed OHKO
+2 40 SpA Kommo-o Clanging Scales vs. 252 HP / 4 SpD Skarmory: 164-193 (49.1 - 57.7%) -- 96.9% chance to 2HKO
+2 40 SpA Kommo-o Clanging Scales vs. 248 HP / 252+ SpD Amoonguss: 205-243 (47.5 - 56.3%) -- guaranteed 2HKO after Stealth Rock and Black Sludge recovery
+2 40 SpA Kommo-o Clanging Scales vs. 0 HP / 0 SpD Rillaboom: 331-390 (97 - 114.3%) -- guaranteed OHKO after Stealth Rock
Max attack can threaten mixed defensive corviknight:
+1 252 Atk Kommo-o Close Combat vs. 252 HP / 132+ Def Corviknight: 202-238 (50.5 - 59.5%) -- guaranteed 2HKO after Stealth Rock and Leftovers recovery
Primarina isn't an amazing switchin either:
+1 252 Atk Kommo-o Close Combat vs. 248 HP / 0 Def Primarina: 167-197 (46 - 54.2%) -- 97.7% chance to 2HKO after Stealth Rock and Leftovers recovery
Physdef corviknight ends up as a major issue even with max attack:
+1 252 Atk Kommo-o Close Combat vs. 252 HP / 252+ Def Corviknight: 183-216 (45.7 - 54%) -- 2.3% chance to 2HKO after Leftovers recovery
Aegislash is a major problem, especially setup or subtoxic:
+2 40 SpA Kommo-o Clanging Scales vs. 0 HP / 4 SpD Aegislash-Shield: 92-108 (35.2 - 41.3%) -- 100% chance to 3HKO after Stealth Rock and Leftovers recovery
The low SpA investment also means +SpD Haze Pex can stop you in your tracks:
+2 40 SpA Kommo-o Clanging Scales vs. 252 HP / 252+ SpD Toxapex: 138-163 (45.3 - 53.6%) -- 92.2% chance to 2HKO after Stealth Rock and Black Sludge recovery
It also means that offensive Volcarona escapes the OHKO, and can set up on you and revenge sweep:
+2 40 SpA Kommo-o Clanging Scales vs. 0 HP / 0 SpD Volcarona: 237-279 (76.2 - 89.7%) -- guaranteed 2HKO
You could fiddle around with the EVs depending on what you think needs more coverage.
Ultimately, Omniboost Kommo-o is going to struggle hard vs fairies no matter how you do, and is very prediction-reliant if against teams with any steel or fairy type - which is to say, most teams - so it's not the most viable option.