UU Victim of the Week! (Week Twenty-Seven: Contrary Serperior)

[Prinz]

Counter

Victini @ Choice Scarf
Ability: Victory Star
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly / Adamant Nature
- V-create
- Bolt Strike
- U-turn
- Trick / Zen Headbutt

Someone already posted the Choice Band set and this set acts as a similiar role against Jirachi, it can switch into every move and then process to force it out, gaining momentum with U-Turn or hitting hard with V-Create if the opponent lacks switch on it. Don't much to say really.

Check

Krookodile (F) @ Choice Scarf
Ability: Intimidate
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Aerial Ace
- Pursuit
- Knock Off
- Earthquake

Unlikely Victini it can't switch on Moonblast without getting wrecked (and on Energy Ball as well) but it can switch on Psyshock, HP Fire and Calm Mind so I would call it a check (not a super one, but you guys already posted the best I guess), and in a similiar as Victini it forces Jirachi out thanks to Knock Off. Nothing much to say here as well I think.

 

[8-BIT Luster]

So when we do our calcs, in order for it to be a counter should we assume that it has to take damage switching in?
Because there's a few things listed as counters that get 3hko'd by +1 LO Rachi and cannot OHKO in return. These Pokemon are also slower, so they can't actually do their job of KOing Rachi. When determining if a mon is a counter, should the benchmark be not getting 3HKO'd by +1 LO Rachi and being able to 2hko in return?

 

[newfren]

You should be assuming that this jirachi gets 1 free turn as you switch in - if it's at +1, then it has used that turn to set up. That means even if you're slower and 2HKO you will beat it as it cannot 2HKO you.

 

[QuietHeatran]

Nominating Scarf Rotom-H as a check:

Rotom-Heat @ Choice Scarf
Ability: Levitate
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Overheat
- Volt Switch
- Trick
- Thunderbolt

The 4 extra EVs should really go into HP but I'm too lazy to rerun my calcs.

As noted above, Superachi is either at +1 or goes for an attack or subs.

If Superachi attacks, Rotom is not OHKO'd and can ohko back given that it is scarfed and thus outspeeds rachi. Proof that it's not ohko'd below:

Leftovers/Expert Belt Calcs:
252 SpA Jirachi Psyshock vs. 0 HP / 0 Def Rotom-H: 103-123 (42.7 - 51%)
252 SpA Jirachi Moonblast vs. 0 HP / 4 SpD Rotom-H: 41-48 (17 - 19.9%)
252 SpA Jirachi Psyshock vs. 0 HP / 0 Def Rotom-H: 103-123 (42.7 - 51%) --
252 SpA Jirachi Hidden Power Fire vs. 0 HP / 4 SpD Rotom-H: 26-31 (10.7 - 12.8%)

Life Orb Calcs:
252 SpA Life Orb Jirachi Psyshock vs. 0 HP / 0 Def Rotom-H: 134-160 (55.6 - 66.3%)
252 SpA Life Orb Jirachi Moonblast vs. 0 HP / 4 SpD Rotom-H: 53-62 (21.9 - 25.7%)
252 SpA Life Orb Jirachi Energy Ball vs. 0 HP / 4 SpD Rotom-H: 51-60 (21.1 - 24.8%)
252 SpA Life Orb Jirachi Hidden Power Fire vs. 0 HP / 4 SpD Rotom-H: 34-40 (14.1 - 16.5%)

whereas:
252 SpA Rotom-H Overheat vs. 0 HP / 4 SpD Jirachi: 366-432 (107.3 - 126.6%)

If Superachi CMs, Rotom-H's countering ability depends on luck and the presence of stealth rock - It can only 2hko with Overheat and thus it has a chance to be ohko'd with sr at +1 from lefties and is straight ohko'd with stealth rock +1 from life orb. For this reason, Rotom-H is more of a check. The option of trick is also a double edged sword, giving superachi a speed boost but forcing it into psyshock and preventing further CMs. This should be an incentive to get the opponent to attack since if the opponent CMs again, rachi has a small chance of surviving the second overheat.

Leftovers/Expert Belt Calcs:
+1 252 SpA Jirachi Psyshock vs. 0 HP / 0 Def Rotom-H: 154-183 (63.9 - 75.9%) -- 6.3% chance to OHKO after Stealth Rock (odds are in your favor but it's down to luck)
+1 252 SpA Jirachi Moonblast vs. 0 HP / 4 SpD Rotom-H: 61-72 (25.3 - 29.8%)
+1 252 SpA Jirachi Energy Ball vs. 0 HP / 4 SpD Rotom-H: 57-68 (23.6 - 28.2%)
+1 252 SpA Jirachi Hidden Power Fire vs. 0 HP / 4 SpD Rotom-H: 38-45 (15.7 - 18.6%)

Life Orb Calcs:
+1 252 SpA Life Orb Jirachi Psyshock vs. 0 HP / 0 Def Rotom-H: 200-238 (82.9 - 98.7%) (so if sr come up, you're possibly screwed)
+1 252 SpA Life Orb Jirachi Moonblast vs. 0 HP / 4 SpD Rotom-H: 79-94 (32.7 - 39%) -- 9.8% chance to 2HKO after Stealth Rock
+1 252 SpA Life Orb Jirachi Energy Ball vs. 0 HP / 4 SpD Rotom-H: 74-88 (30.7 - 36.5%) -- guaranteed 3HKO after Stealth Rock (no chance to 2hko since max from two hits is 73% - just missing the 2hko postrocks)
+1 252 SpA Life Orb Jirachi Hidden Power Fire vs. 0 HP / 4 SpD Rotom-H: 49-58 (20.3 - 24%) -- guaranteed 4HKO after Stealth Rock

whereas:
252 SpA Rotom-H Overheat vs. +1 0 HP / 4 SpD Jirachi: 246-290 (72.1 - 85%)
-2 252 SpA Rotom-H Overheat vs. +1 0 HP / 4 SpD Jirachi: 122-146 (35.7 - 42.8%)

So if the opponent attacks, it's a minimum of 105.8% damage, which is an almost guaranteed 2hko (lefties recovery and abysmally low rolls could let rachi survive). Now if the opponent gets cheeky and tries to CM again:

252 SpA Rotom-H Overheat vs. +1 0 HP / 4 SpD Jirachi: 246-290 (72.1 - 85%)
-2 252 SpA Rotom-H Overheat vs. +2 0 HP / 4 SpD Jirachi: 92-110 (26.9 - 32.2%)

So you have to rely on a high roll on one of those attacks but worst case scenario, Jirachi will be left so weak that the weakest priority move will kill it.

If Superachi subs, you're mildly screwed (why rotom-H is a check, not a counter). Volt Switch breaks the sub but you have to let Rachi get a free CM or attack off. So best case, you sac something (on offense) or phaze something (on stall) or switch to a slowturner (on volt turn) to get rotom back in without damage or to get Jirachi out.

On unpredictability:
Fact is, Rotom-H checks normal Jirachi too. First off, being an electric type it is immune to paralysis. Second Jirachi does very little with Iron Head and has to predict to use zen headbutt (which can lead to mindgames if you have a dark type) and some don't even carry zen headbutt. Plus ZH doesn't 2HKO on Jolly ScarfRachi without rocks 96.1% of the time. So if you can come in on iron head, you can OHKO Adamant scarfrachi with probability greater than 92.2% (Probability of getting one turn without flinch assuming Rachi always get maximum damage rolls - equivalently, assuming a 6hko after rocks). The reason it's only a check is because zen headbutt with proper prediction can 2hko rotom while it might not nab the ohko on bulky rachi and is outsped by scarf rachi (by just one point if scarfrachi's adamant).

Most of the calcs are repeats, I'll just show off the ones for bulky Jirachi and the power of iron head against rotom-H:

Jirachi attacking calcs:

252 Atk Jirachi Iron Head vs. 0 HP / 0 Def Rotom-H: 25-30 (10.3 - 12.4%)
252+ Atk Jirachi Iron Head vs. 0 HP / 0 Def Rotom-H: 28-33 (11.6 - 13.6%)

252 Atk Jirachi U-turn vs. 0 HP / 0 Def Rotom-H: 30-36 (12.4 - 14.9%)
252+ Atk Jirachi U-turn vs. 0 HP / 0 Def Rotom-H: 33-39 (13.6 - 16.1%)

252 Atk Jirachi Body Slam vs. 0 HP / 0 Def Rotom-H: 73-87 (30.2 - 36%) -- guaranteed 3HKO after Stealth Rock
252+ Atk Jirachi Body Slam vs. 0 HP / 0 Def Rotom-H: 80-95 (33.1 - 39.4%) -- 21.5% chance to 2HKO after Stealth Rock

252 Atk Jirachi Zen Headbutt vs. 0 HP / 0 Def Rotom-H: 103-123 (42.7 - 51%) -- guaranteed 2HKO after Stealth Rock (3.9% chance to 2HKO without rocks)
252+ Atk Jirachi Zen Headbutt vs. 0 HP / 0 Def Rotom-H: 114-135 (47.3 - 56%) -- 79.3% chance to 2HKO (outright)

Rotom-H attacking calcs:

252 SpA Rotom-H Overheat vs. 252 HP / 4 SpD Jirachi: 366-432 (90.5 - 106.9%) -- 43.8% chance to OHKO (OHKO after stealth rocks and guaranteed 2hko)
252 SpA Rotom-H Volt Switch vs. 252 HP / 4 SpD Jirachi: 99-117 (24.5 - 28.9%) (So breaks sub with high probability=81.3%)

Rotom-H also isn't entirely garbage in UU. It's a niche pokemon but it can be pretty cool on volt-turn teams and such. Of course when you have Victini as a hard counter to superachi, it's tough for Rotom-H to stand out as a counter :P But rotom-H does have a nice niche as a check that doesn't fear paralysis, even from body slam on account of typing so it doesn't have to fear too much is superachi if regular rachi in disguise.

 

[8-BIT Luster]

You should be assuming that this jirachi gets 1 free turn as you switch in - if it's at +1, then it has used that turn to set up. That means even if you're slower and 2HKO you will beat it as it cannot 2HKO you.

Alright.
That clears stuff up

 

[CoolStoryBrobat]

Zzzz...top 3 counters & checks to Superachi are listed (no specific order):

Top 3 Counters:

Mega Aggron - canasian
Metagross - Professional2341
Jirachi - hilarious

Top 3 Checks:

Victini - Jellied Eels
Dugtrio - dingbat
Houndoom - Bluwing

Next Victim is something that you almost never see these days for some weird reason...

Set name: Physical Sweeper Meloetta
name: Physical Sweeper
move 1: Relic Song
move 2: Close Combat
move 3: Knock Off
move 4: Return / Zen Headbutt
ability: Serene Grace
item: Life Orb
evs: 252 Atk / 4 SpD / 252 Spe
nature: Jolly / Adamant

 

[President Shinra]

Reserving Sableye (I'll write it tomorrow)

 

[canasian]

Counter:

Granbull @ Leftovers
Ability: Intimidate
EVs: 252 HP/4 Atk/252 Def
Impish Nature
- Play Rough
- Rest
- Sleep Talk
- Heal Bell

Granted, Granbull doesn't really want to switch into a Meloetta-Aria forme, so it takes some scouting before it can switch in, but once you're certain it's the physical set:
-1 252+ Atk Life Orb Meloetta-P Return vs. 252 HP / 252+ Def Granbull: 136-161 (35.4 - 41.9%) -- 85.3% chance to 3HKO after Leftovers recovery

It can even deal with the sleep chance from Relic Song thanks to Sleep Talk.

4 Atk Granbull Play Rough vs. 0 HP / 0 Def Meloetta-P: 248-294 (72.7 - 86.2%) -- guaranteed 2HKO (it's a guaranteed OHKO if Meloetta uses Close Combat)

 

[dingbat]

Reserving Spiritomb as Counter

Gah, nvm. Someone else can take it since I definitely won't be able to write it in 6 hrs :/

 

[Nysyr]

Highly recommend Slashing thunder over Return/Zen on that Melo, since it removes far more options to switch in on it.

Check/Counter to this thing depending on whether you are mega Evo'd at the time or not, also assuming you switch in on non-Pirouette form; Mega VS relic Song is really weird to try and deal with.

Aerodactyl @ Aerodactylite
Ability: Unnerve
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Pursuit
- Aerial Ace
- Stone Edge
- Roost

Didn't screw with the EVs very much. Obviously being Evo'd beforehand is infinitely better.

Blegh, just sac a ghost if you care about this thing being dead imo.

Defensive set can also counter this thing 100% assuming no SR on your side of field 100%

Hide

Aerodactyl @ Aerodactylite
Ability: Pressure
EVs: 248 HP / 124 Def / 136 Spe
Jolly Nature
- Aerial Ace
- Taunt
- Stealth Rock
- Roost

 

[President Shinra]

mezomi I already reserved it, pick something else :(

 

[mezomi]

Ahh sorry, I skipped over that post.

 

[Sage]

View attachment 24990
Based Counter Cress
Cresselia (F) @ Rocky Helmet
Ability: Levitate
EVs: 252 HP / 252 Def / 4 SpA
Bold Nature
- Psyshock
- Moonlight
- Toxic
- Moonblast/Thunder Wave/Lunar Dance

Cress vs Meloetta
0 SpA Cresselia Psyshock vs. 0 HP / 0 Def Meloetta-P: 150-176 (43.9 - 51.6%) -- 7.8% chance to 2HKO (this always kills with 2 rounds of LO recoil)

0 SpA Cresselia Psyshock vs. -1 0 HP / 0 Def Meloetta-P: 222-264 (65.1 - 77.4%) -- guaranteed 2HKO (after a Close Combat)

Meloeta vs Cress
252+ Atk Life Orb Meloetta-P Return vs. 252 HP / 252+ Def Cresselia: 149-177 (33.5 - 39.8%) -- guaranteed 3HKO

252+ Atk Life Orb Meloetta-P Close Combat vs. 252 HP / 252+ Def Cresselia: 87-104 (19.5 - 23.4%) -- possible 5HKO

252+ Atk Life Orb Meloetta-P Knock Off (97.5 BP) vs. 252 HP / 252+ Def Cresselia: 190-226 (42.7 - 50.9%) -- 3.9% chance to 2HKO

252+ Atk Life Orb Meloetta-P Knock Off vs. 252 HP / 252+ Def Cresselia: 130-153 (29.2 - 34.4%) -- 4.8% chance to 3HKO

OK so worst case scenario Meloetta is alrady in P forme, and it Knocks off on your Switch in. Now it's done almost half of your health. Proceed to Moonlight as you sponge anything it has left and it kills itself with Life Orb Recoil. Obviously if your crit early on then bye bye cress but this is in a straight game. There is almost nothing that counters this, didn't wanna go Aromatisse since someone did Granbull right above me, and it has a hrad time with other Meloetta variants. Cresselia beats everything but Specs and Sub CM (with this set, some beat specs) so there's that, less scouting required.

 

[RufflesPro]

Hippowdon an counter

Hippowdon @ Leftovers
Ability: Sand Stream
EVs: 252 HP / 4 Atk / 252 Def
Impish Nature
- Slack Off
- Earthquake
- Stealth Rock
- Toxic / Whirlwind

Phys. Defensive Hippo, simple, it sets up rocks too, and spreads toxic or whirlwind pokemons setting up.

This is how you win vs. Meloetta-P: Switch on it, keep slacking off until it's -2 from CC (or in range of eq after Return's LO recoil and sandstorm) and then EQ which OHKOs because sandstorm and LO. Simple af.

252+ Atk Life Orb Meloetta-P Close Combat vs. 252 HP / 252+ Def Hippowdon: 177-211 (42.1 - 50.2%) -- 0.4% chance to 2HKO after Stealth Rock and Leftovers recovery
252+ Atk Life Orb Meloetta-P Return vs. 252 HP / 252+ Def Hippowdon: 152-179 (36.1 - 42.6%) -- guaranteed 3HKO after Stealth Rock and Leftovers recovery

4 Atk Hippowdon Earthquake vs. -2 0 HP / 0 Def Meloetta-P: 261-307 (76.5 - 90%) -- guaranteed 2HKO after sandstorm damage (Basically guaranteed after LO)

Enjoy ༼ •ᴥ•༽

 

[JustAMan]

View attachment 24990
Based Counter Cress
Cresselia (F) @ Rocky Helmet
Ability: Levitate
EVs: 252 HP / 252 Def / 4 SpA
Bold Nature
- Psyshock
- Moonlight
- Toxic
- Moonblast/Thunder Wave/Lunar Dance

Cress vs Meloetta
0 SpA Cresselia Psyshock vs. 0 HP / 0 Def Meloetta-P: 150-176 (43.9 - 51.6%) -- 7.8% chance to 2HKO (this always kills with 2 rounds of LO recoil)

0 SpA Cresselia Psyshock vs. -1 0 HP / 0 Def Meloetta-P: 222-264 (65.1 - 77.4%) -- guaranteed 2HKO (after a Close Combat)

Meloeta vs Cress
252+ Atk Life Orb Meloetta-P Return vs. 252 HP / 252+ Def Cresselia: 149-177 (33.5 - 39.8%) -- guaranteed 3HKO

252+ Atk Life Orb Meloetta-P Close Combat vs. 252 HP / 252+ Def Cresselia: 87-104 (19.5 - 23.4%) -- possible 5HKO

252+ Atk Life Orb Meloetta-P Knock Off (97.5 BP) vs. 252 HP / 252+ Def Cresselia: 190-226 (42.7 - 50.9%) -- 3.9% chance to 2HKO

252+ Atk Life Orb Meloetta-P Knock Off vs. 252 HP / 252+ Def Cresselia: 130-153 (29.2 - 34.4%) -- 4.8% chance to 3HKO

OK so worst case scenario Meloetta is alrady in P forme, and it Knocks off on your Switch in. Now it's done almost half of your health. Proceed to Moonlight as you sponge anything it has left and it kills itself with Life Orb Recoil. Obviously if your crit early on then bye bye cress but this is in a straight game. There is almost nothing that counters this, didn't wanna go Aromatisse since someone did Granbull right above me, and it has a hrad time with other Meloetta variants. Cresselia beats everything but Specs and Sub CM (with this set, some beat specs) so there's that, less scouting required.

However, it is still quite risky, as you must be healty, and even then, there is a chance of 2HKO after Rocks ( u know, no lefties)
More precisely, Knock Off + Return deal 76.2 min and 90.7 max.
So, your cress, assuming Rocks, must be at least at 88.3 percent to survive the min roll, while max and near max KO after Rocks. Even if Return is used first, your Cress must have at least 97.4 of its health to avoid the 2HKO.
Soft, veery soft counter.
This applies to hippo too.

 

[Sage]

However, it is still quite risky, as you must be healty, and even then, there is a chance of 2HKO after Rocks ( u know, no lefties)
More precisely, Knock Off + Return deal 76.2 min and 90.7 max.
So, your cress, assuming Rocks, must be at least at 88.3 percent to survive the min roll, while max and near max KO after Rocks. Even if Return is used first, your Cress must have at least 97.4 of its health to avoid the 2HKO.
Soft, veery soft counter.
This applies to hippo too.

This has been gone over before counters are always at 100% health and hazards are cleared. Also if you wanted to be realistic Meloetta Relic Songs on the switch in and you are in a great position. This has always been a theory mon, and just run lefties if it's that big of an issue for you.

 

[President Shinra]

Hello I'm a Counter (Sableye) @ Leftovers
Ability: Prankster
EVs: 252 HP / 252 SpD / 4 Spe
Careful Nature
- Taunt
- Will-O-Wisp
- Knock Off
- Recover

Sableye is without a doubt one of the best counters to Physical Sweeper Meloetta. Why? Well, there are many reasons, but one of the most important ones is its typing. The reason its typing is so important is because by coming in on Meloetta's first turn of attacking, Sableye's ghost typing stops the Relic Song and keeps Meloetta in base form, stifling anything it can do and easily forcing it out. Even if the Meloetta predicts your Sableye switch and goes for Knock Off, it's still not going to inflict a lot of damage, and would do even less if Meloetta's burned.

252 Atk Life Orb Meloetta Knock Off (97.5 BP) vs. 252 HP / 0 Def Sableye: 123-146 (40.4 - 48%) -- guaranteed 3HKO after Leftovers recovery
252 Atk Life Orb burned Meloetta Knock Off (97.5 BP) vs. 252 HP / 0 Def Sableye: 61-73 (20 - 24%) -- possible 6HKO after Leftovers recovery
252 Atk Life Orb Meloetta Knock Off vs. 252 HP / 0 Def Sableye: 82-97 (26.9 - 31.9%) -- guaranteed 4HKO

That damage definitely cannot get past Prankster Recover. And, Sableye can hit back by 2HKOing with Knock Off.

0 Atk Sableye Knock Off (97.5 BP) vs. 0 HP / 0 Def Meloetta: 204-242 (59.8 - 70.9%) -- guaranteed 2HKO

GG Physical Sweeper Meloetta.

 

[CoolStoryBrobat]

This has been gone over before counters are always at 100% health and hazards are cleared. Also if you wanted to be realistic Meloetta Relic Songs on the switch in and you are in a great position. This has always been a theory mon, and just run lefties if it's that big of an issue for you.

Actually to be a counter at least Stealth Rock has to be factored in, just future ref

 

[JustAMan]

This has been gone over before counters are always at 100% health and hazards are cleared. Also if you wanted to be realistic Meloetta Relic Songs on the switch in and you are in a great position. This has always been a theory mon, and just run lefties if it's that big of an issue for you.

Point taken, still you don't know what melo is till it rsongs / does something else, so aunless Cress happens to be a surefire counter to ALL the sets, a player may disguise melo's set and have it vs cress switch in Pirouette. Then, it is theorymoning.
However, yup, if it switches into rsong, then u r right.
EDIT: President Shinra, the calc is on Aria I guess.

 

[Sage]

Actually to be a counter at least Stealth Rock has to be factored in, just future ref

OK, but i guess we should assume it has to Relic Song first than? Idk its hard to account for form switching, but good to know of stealth rocks, and JustAman Cresselia deals with every other Meloetta set IK except for Sub CM and Specs Dark Pulse/Shadow Ball (needs different EVs, but can take those too)

 

[8-BIT Luster]

meloetta-P is too damn fast

 

[DiscoDucky]

Reserving mega banette.as a counter

 

[Xyldaz]

Doublade as a counter check

Doublade @ Eviolite
Ability: No Guard
EVs: 240 HP / 252 Def / 16 SpD
Impish Nature
- Shadow Claw
- Rest
- Sleep Talk
- Sacred Sword

RestTalk Doublade is a good pokemon on stall and it's a cool answer to Meloetta-P. It's only 3HKOed by Knock Off even if Melo is Adamant, while it can 2HKO it with Sacred Sword. It can also stop Meloetta from turning into Pirouette form as it's immune to Relic Song, and even if it stays in its basic form it does pitiful damage to Doublade which has semi-reliable recovery.

Calcs:
252+ Atk Life Orb Meloetta-P Knock Off (97.5 BP) vs. 240 HP / 252+ Def Eviolite Doublade: 109-130 (34.1 - 40.7%) -- guaranteed 3HKO after Stealth Rock
252+ Atk Life Orb Meloetta Knock Off (97.5 BP) vs. 240 HP / 252+ Def Eviolite Doublade: 78-94 (24.4 - 29.4%) -- guaranteed 4HKO after Stealth Rock

0 Atk Doublade Sacred Sword vs. 0 HP / 0 Def Meloetta-P: 154-182 (45.1 - 53.3%) -- 89.5% chance to 2HKO after Stealth Rock
0 Atk Doublade Sacred Sword vs. 0 HP / 0 Def Meloetta: 87-103 (25.5 - 30.2%) -- guaranteed 4HKO

EDIT: Sleep talk is pretty unreliable so it's rather a check than a counter, my bad.

 

[8-BIT Luster]

We're assuming Meloetta is already Pirouette when it comes out.

Also reserving Spiritomb

 

[8-BIT Luster]

Spiritomb is a based af counter to Meloetta-P. Since dingbat never wrote it up, I decided to take it, as I really wanted to submit it anyways.

Spiritomb @ Leftovers
Ability: Infiltrator
EVs: 248 HP / 252 Def / 8 SpA
Bold Nature
IVs: 0 Atk
- Sleep Talk
- Rest
- Dark Pulse
- Calm Mind

CroTomb is such a bulky Pokemon, and Meloetta just cannot break through it. Even with Meloetta-P resisting Spiritomb's Dark pulse, Spiritomb can still take it on.

252+ Atk Life Orb Meloetta-P Knock Off (97.5 BP) vs. 248 HP / 252+ Def Spiritomb: 103-121 (33.9 - 39.9%) -- 32.5% chance to 3HKO after Leftovers recovery
Everything else does no damage to t.
Once Meloetta has removed Spiritomb's Leftovers, its Knock Off becomes pitifully weak, and Spritomb can set up in its face with impunity.
252+ Atk Life Orb Meloetta-P Knock Off vs. 248 HP / 252+ Def Spiritomb: 69-82 (22.7 - 27%) -- 40.1% chance to 4HKO

And once Spiritomb gets maxed out on SpA, this happens:
+6 8 SpA Spiritomb Dark Pulse vs. 0 HP / 4 SpD Meloetta-P: 199-235 (58.3 - 68.9%) -- guaranteed 2HKO
Meloetta cannot 3HKO Spiritomb with any of its moves, as Knock Off's 97.5 base damage is contingent upon the opponent having an item.

CroTomb can also function with its item knocked off.