Project Threats to OU Cores v3: Round 7 1/2: short hiatus

[RequinBleu]

Tornadus-Therian (M) @ Rocky Helmet
Ability: Regenerator
EVs: 216 HP / 100 Def / 192 Spe
Timid Nature
- Taunt
- Hurricane
- Knock Off
- Defog

Tornadus-T is usually the best answer in Bulky Offense against rain.
Indeed Tornadus-T can't miss Hurrican under the rain and make good damage also Knock Off with Taunt allow to remove item of Pelliper and prevent Entry Hazard of Ferrothorn. After the taunt, Ferrothorn is forced to use Gyro Ball and take damage of Rocky Helmet or give a free switch for another Pokemon.

 

[erz]

Nice round everyone, the core was relatively hard to threaten because it's effectiveness also relies on them taking damage or sacking them to then enable their teammates to break through the opposing team. Thus the threats of the round will be the ones that are the safest and the most reliable options

Last Round's Analysis

Threats of the Round:

:One of the best mons against this core, changing weather against a weather based team is one of the most proven strategies and this one oneshots one member of the core and wins against the other as well. As long as you don't rush your mega-timing this is super safe.

: zone traps ferro, kills peli. Not much to say about this one, it can also stall rainturns by repeatedly subbing up. Trapping the most essential pivot on rain is great. electrium or steelium wouldn't make a difference on this one. good post

: nice suggestion, the submitted set puts up a ton of pressure and uses the 2 members of the core as a way to get a +1 in spA. Ferro usually is the best switchin to this on rain so bop.

Additional Notes:

: megazam surely is super threatening against rain but against this core aka. the defensive backbone of rain it relies on hitting focus blasts against ferro. Thanks for posting this, just not threat of the round as it was a less safe option.

: given set outright wins against this core, not threat of the round because it is very hard to fit on teams and is a very niche pick if you consider the reflect type option.

: sad you only reserved but im featuring this anyway as it clicks a button and drops one. Potentially ferro can come in, go peli on the z and then kill it but at least 1 is always dropping.

Short Notes on other Submissions:

Zapdos does the same as zone, proves a better switchin because recovery and keeps hazards off the field. But basically every rain team features mpert which will make this less good in practice as it does not trap ferro. Serp doesnt ohko peli from the start so it eats a hurricane and it needs boosts to kill ferro so it will take a gyro ball as well. MSab is cool against this core but in practice struggles with rain abusers; depends on what your pair it with to make it really troublesome (look: chansey, pex, etc.). Torn sure is a great pivot against rain but takes a lot from rain-boosted scalds and takes 50-60 from gyro. Thus relies on it's teammates. Thanks for posting everyone

Round 3 Core: Medicham-Mega + Tapu Koko

Here are the sets

Medicham-Mega @ Medichamite
Ability: Telepathy
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Fake Out
- High Jump Kick
- Ice Punch
- Thunder Punch

Tapu Koko @ Shuca Berry
Ability: Electric Surge
EVs: 32 HP / 88 Def / 172 SpA / 216 Spe
Timid Nature
- Thunderbolt
- Volt Switch
- Hidden Power [Ice]
- Roost

• This is the core of MediKoko offenses. When posting threats focus on what would work best in a real battle scenario! Tapu Koko helps Medi as it boosts it's Thunder Punch that lets it break through MegaSab, pex and others. Koko also lures ground-types that would revenge both of them normally.
• Try to post only OU viable Pokémon and don't post sets specifically for this core. Additionally, your threat should not be complete deadweight against teams that do not Medicham-Mega + Tapu Koko. Keep in mind what pokemon are commonly paired with those two! Have a great day everyone!

 

[Solaros & Lunaris]

Scarf Vic

 

[Katy]

tapu lele


Tapu Lele @ Choice Scarf
Ability: Psychic Surge
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Psychic
- Moonblast
- Hidden Power Fire
- Focus Blast

Choice Scarfed Tapu Lele is a good option against both because it can come in on Mega Medichams Fake Out and block the priority move with its Psychic Terrain, furthermore it is capable of blocking
other possible priority moves which the opposing team might have as well. Tapu Lele can come into any moves of Mega Medicham, it withstands a HJK due to its 4x resist to fighting-type moves and
can revenge kill Mega Medicham easily with either STAB Psychic or a STAB Moonblast.
Moonblast does also a decent chunk to Tapu Koko wearing it down too as it has to Roost up the damage
Also on top of that, Tapu lele can change the terrain from electric terrain to psychic terrain making Mega Medichams Thunder Punch not able to OHKO Tapu Lele in the process.

Calcs:

Hide

Mega Medi vs Lele:
252 SpA Tapu Lele Psychic vs. 0 HP / 0 SpD Medicham-Mega in Psychic Terrain: 253-298 (96.9 - 114.1%) -- guaranteed OHKO after Stealth Rock
252 SpA Tapu Lele Moonblast vs. 0 HP / 0 SpD Medicham-Mega: 356-422 (136.3 - 161.6%) -- guaranteed OHKO

Medicham-Mega Fake Out vs. Tapu Lele in Psychic Terrain: 0-0 (0 - 0%) -- possibly the worst move ever
252 Atk Pure Power Medicham-Mega High Jump Kick vs. 0 HP / 0 Def Tapu Lele: 112-132 (39.8 - 46.9%) -- 41.4% chance to 2HKO after Stealth Rock
252 Atk Pure Power Medicham-Mega Ice Punch vs. 0 HP / 0 Def Tapu Lele: 173-204 (61.5 - 72.5%) -- guaranteed 2HKO after Stealth Rock
252 Atk Pure Power Medicham-Mega Thunder Punch vs. 0 HP / 0 Def Tapu Lele: 173-204 (61.5 - 72.5%) -- guaranteed 2HKO after Stealth Rock

Tapu Koko vs Lele:
252 SpA Tapu Lele Psychic vs. 32 HP / 0 SpD Tapu Koko: 186-220 (64.3 - 76.1%) -- guaranteed 2HKO after Stealth Rock
252 SpA Tapu Lele Moonblast vs. 32 HP / 0 SpD Tapu Koko: 198-234 (68.5 - 80.9%) -- guaranteed 2HKO after Stealth Rock

172 SpA Tapu Koko Thunderbolt vs. 0 HP / 4 SpD Tapu Lele in Electric Terrain: 148-175 (52.6 - 62.2%) -- guaranteed 2HKO after Stealth Rock
172 SpA Tapu Koko Volt Switch vs. 0 HP / 4 SpD Tapu Lele in Electric Terrain: 115-136 (40.9 - 48.3%) -- 70.3% chance to 2HKO after Stealth Rock
172 SpA Tapu Koko Hidden Power Ice vs. 0 HP / 4 SpD Tapu Lele: 44-52 (15.6 - 18.5%) -- possible 5HKO after Stealth Rock

 

[Tysonslayer]

Tapu Bulu @ Leftovers
Ability: Grassy Surge
EVs: 248 HP / 8 Def / 252 SpD
Careful Nature
- Bulk Up
- Horn Leech
- Superpower
- Protect

Tapu Bulu is already an amazing counter against Tapu Koko and can easily take hits from hit Tapu Koko always forcing it to Volt Switch into someone else to try and break Tapu Bulu , this usually leads him into getting a free turn to recover or begin setting up so he can deal lots of damage to whatever is coming in. After Tapu Koko is Volt Switching into Mega Medicham Tapu Bulu gets a chance to Bulk Up and increase his defense stat which makes it a lot easier to handle this core due to the defense boost makes it easier to beat Medicham since the only real threatening move of Medicham is Ice Punch, which is a 3HKO with the defense boost, and can then keep on setting up to +2 to ensure he never dies against Medicham or just go straight for the kill

 

[VCrakeV]

"Tapu Koko helps Medi as it boosts it's Thunder Punch that lets it break through MegaSab"

I understand this is with reference to SpD sets, but I can't help but find it funny that Mega Sableye can check a threat that is suppose to break it:

Sableye-Mega @ Sablenite
Ability: Prankster
EVs: 248 HP / 252 Def / 8 Spe
Bold Nature
IVs: 0 Atk
- Calm Mind
- Shadow Ball
- Recover
- Protect

Max defense allows Sableye to check Mega Medicham:

252 Atk Pure Power Medicham-Mega Thunder Punch vs. 248 HP / 252+ Def Sableye-Mega in Electric Terrain: 127-150 (41.9 - 49.5%) -- guaranteed 3HKO

Protect allows Sableye to Mega evolve safely, and also provides a way to stall out electric terrain to take hits better. Calm mind gives Sableye some much needed offensive presence, while simultaneously boosting its SpD so Sableye can wall more threatening special attackers the more boosts it gets, like Koko, Greninja, Heatran, and Tornadus. Shadow ball is chosen over dark pulse to hit Medicham and Koko harder, as well as other fairies, like Fini.

 

[Stall is coming]

Reserving VenusaurM

Venusaur @ Venusaurite
Ability: Chlorophyll
EVs: 252 HP / 172 Def / 68 SpD / 16 Spe
Bold Nature
- Giga Drain
- Sludge Bomb
- Hidden Power Fire
- Synthesis

Calcs:

172 SpA Tapu Koko Thunderbolt vs. 252 HP / 68 SpD Venusaur-Mega in Electric Terrain: 67-79 (18.4 - 21.7%) -- possible 5HKO
252 Atk Pure Power Medicham-Mega High Jump Kick vs. 252 HP / 172+ Def Venusaur-Mega: 117-138 (32.1 - 37.9%) -- 93.8% chance to 3HKO

0 SpA Venusaur-Mega Sludge Bomb vs. 32 HP / 0 SpD Tapu Koko: 290-344 (100.3 - 119%) -- guaranteed OHKO
0 SpA Venusaur-Mega Sludge Bomb vs. 0 HP / 0 SpD Medicham-Mega: 132-156 (50.5 - 59.7%) -- guaranteed 2HKO

Medicham has the 4move syndrome, either he uses tpunch, either he uses psy stab.
In the first case, Medicham and Tapu Koko are countered by Mega-Venusaur.

ps: Somebody, please, have the guts to choose Lighting Rod A-Marowak

 

[superstrike66]

Sand Rush Excadrill

Excadrill @ Steelium Z
Ability: Sand Rush
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Swords Dance
- Earthquake
- Iron Head
- Rapid Spin​

Excadrill needs sand support to beat this core. Under Sand, Excadrill is able to outspeed and OHKO Medicham with Z-Steel. Drill then 2HKOs Koko with EQ, While Koko can only HP Ice, which 5HKOs.

Calcs VS

:​

252 Atk Excadrill Corkscrew Crash (160 BP) vs. 0 HP / 4 Def Medicham-Mega: 306-361 (117.2 - 138.3%) -- guaranteed OHKO

Calcs VS

:
​

252 Atk Excadrill Earthquake vs. 32 HP / 88 Def Shuca Berry Tapu Koko: 174-205 (60.2 - 70.9%) -- guaranteed 2HKO
172 SpA Tapu Koko Hidden Power Ice vs. 4 HP / 0 SpD Excadrill: 70-83 (19.3 - 22.9%) -- possible 5HKO

 

[wadusher]

Lopunny @ Lopunnite
Ability: Limber
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Return
- High Jump Kick
- Fake Out
- Ice Punch / Quick attack / Power up punch

Boasting a faster fake out and the ability to outspeed Tapu Koko, lopunny here becomes a huge obstacle once it actually manages to get in. Medicham dies from full to fake out + return, while koko only needs a little bit of chip to do the same, though you will need u-turn support and possibly some clever double switching, but that's nothing new for this mon.

calcs

252 Atk Lopunny-Mega Fake Out vs. 0 HP / 4 Def Medicham-Mega: 78-93 (29.8 - 35.6%) -- 25.1% chance to 3HKO
252 Atk Lopunny-Mega Return vs. 0 HP / 4 Def Medicham-Mega: 196-232 (75 - 88.8%) -- guaranteed 2HKO

252 Atk Lopunny-Mega Return vs. 32 HP / 88 Def Tapu Koko: 178-211 (61.5 - 73%) -- guaranteed 2HKO
252 Atk Lopunny-Mega Fake Out vs. 32 HP / 88 Def Tapu Koko: 70-84 (24.2 - 29%) -- 99.2% chance to 4HKO

172 SpA Tapu Koko Thunderbolt vs. 0 HP / 4 SpD Lopunny-Mega in Electric Terrain: 171-202 (63 - 74.5%) -- guaranteed 2HKO

 

[JCVD is forever]

Tapu Koko @ Electrium Z
Ability: Electric Surge
EVs: 20 HP / 252 SpA / 20 SpD / 216 Spe
Timid Nature
- Thunderbolt
- Toxic
- Roost
- U-turn

Thanks to Toxic, this Tapu Koko set is able to cripple the opposing Koko and put it on a timer, thus winning the match-up as it can easily recover the damages inflicted by Thunderbolt thanks to Roost. It is also able to OHKO Mega-Medicham with Gigavolt Havoc.

252 SpA Tapu Koko Gigavolt Havoc (175 BP) vs. 0 HP / 0 SpD Medicham-Mega in Electric Terrain: 397-468 (152.1 - 179.3%) -- guaranteed OHKO

Thus, Toxic Tapu Koko is a great answer to the M-Medicham - Shuca Koko core.

Even outside of this match-up, toxic can be used to cripple most of Koko's usual counter, such as assault vest Tangrowth, Specially defensive Bulu or Gastrodon.

 

[Ahy Wddicted]

Gastrodon @ Leftovers
Ability: Storm Drain
EVs: 252 HP / 4 Def / 252 SpD
Sassy Nature
- Recover
- Toxic / Clear Smog
- Scald
- Earthquake / Protect

Simply regular shuca berry Tapu Koko can’t touch Gastrodon, Medicham-Mega can’t free switch in because of burn or toxic. This situation lure opponents easy-predictable doubling and could get a nice position in entire game.

 

[erz]

Sorry this took a while, have been busy for a bit. Anyway medikoko is a common core that's getting countered by picks that got a bit less popular recently. Interesting threats you people have posted, lets get right into it

Last Round's Analysis

Threats of the Round:

: mvenu has become very rare to the point that it's definitly underrated. There's no way to get around this thing for the core as long as hjk doesn't crit twice on venu coming in on rocks. pretty safe and a cool pick into the metagame. Thanks for posting

: scarf lele doesn't necessarily come in any of those two but it oneshots both with psychic when psychic terrain is up and it can technically click moonblast because it always lives a koko attack. Little counterplay to this one on offensive teams, very threatening

: the posted tapu koko set is a good pick in the metagame and defeats this core pretty comfortably. Don't necessarily switch it in on medi attacks or volt switches as it either takes a huge chunk or is getting chipped on but in extreme situations you can rely on it always living a hit. Also easily wins the 1v2's.

Additional Notes:

: Very threatening. However this can technically be said about most weather abusers like megapert, kingdra or ashninja. They're all rely on support though and sometimes even on sacking the weather-enabler which opens up for counterplay.

: can't come in on either of the two and it needs fake out damage on both to be able to ko them with return. Does work very well in a realistic scenario though because lopunny is generally very hard to switch into for offense/HO

Short Notes on other Submissions:

While I would've agreed to some other bulu sets I dont think the specific one does well against this core. Obviously it can come in on tbolts and then threaten the core with horn leech but in a realistic scenario the koko will almost always volt switch on bulu coming in. Also can't come in on medi as even hjk +ice punch have a good chance to knock out this bulu after a protect on coming in on no rocks. With rocks it's a guaranteed kill. Bulu in general is a nuisance for sure though. maxdef sableye is a bad pick in the meta and also sacrifices it's ability to counter koko just so it can counter medicham. gastrodon sure does well against koko and while it is true medicham takes a lot from switching in.. a medi hjk obliberates it from full.

Round 4 Core: Latias-Mega + Clefable

Here are the sets

Latias-Mega @ Latiasite
Ability: Levitate
EVs: 248 HP / 8 Def / 252 Spe
Timid Nature
IVs: 0 Atk
- Calm Mind
- Roost
- Stored Power
- Ice Beam

Clefable @ Life Orb
Ability: Magic Guard
EVs: 80 HP / 252 SpA / 176 Spe
Modest Nature
IVs: 0 Atk
- Moonblast
- Thunderbolt
- Fire Blast
- Soft-Boiled

• This core has recently gained attraction as it was featured in a lot of balance builds. MegaLatias' status has went up to top-tier-threat and Clefable's usage rose as it's set got explored a bit further and people realized how good it actually is. The core is commonly paired with steel-types on balance teams and proves especially effective on entry hazard centered teams.
• Try to post only OU viable Pokémon and don't post sets specifically for this core. Additionally, your threat should not be complete deadweight against teams that do not feature latias-mega and clefable. Keep in mind what pokemon are commonly paired with those two! Have a great day everyone!

 

[xapx]

Reserving double dance mage

 

[Jordy]

Scizor @ Scizorite
Ability: Light Metal
EVs: 248 HP / 16 Def / 244 SpD
Impish Nature
- Swords Dance
- Bullet Punch
- Roost
- Knock Off

Mega Scizor is quite annoying for this core to deal with. It can easily get free turns off of Mega Latias to set up, and while it can't switch into Clefable, it can easily OHKO it with a boosted Bullet Punch. However, you should be wary of Magnezone, which this core is sometimes paired up with.

 

[Katy]

bulky volc


Volcarona @ Buginium Z
Ability: Flame Body
EVs: 248 HP / 112 Def / 148 Spe
Timid Nature
- Quiver Dance
- Flamethrower
- Bug Buzz
- Roost

Volcarona can set-up on both these members due to its high special defense and Quiver Dance helping the high special defense even further. It also boosts the good special attack and the speed, so it is
able to outspeed after 1 Quiver Dance Mega-Latias. Also both member don't want to stay in on this Volcarona as Volcarona can use both as set-up fodder for its own Quiver Dance.
Bulky Quiver Dance Volcarona also resists the Ice Beam from Mega-Latias, and resists the Moonblast which Clefable packs in its moveslot. Thunderbolt won't do much either same as Fire Blast because
Volcarona takes only neutral damage from the latter of these two mentioned moves.
Also Buginium Z Bug Buzz is a really big threat even to this bulky version of Mega-Latias as Mega-Latias won't take it well and has to use Roost on a neutral Bug Buzz whereas Mega-Latias will get
OHKOed by a neutral Savage-Spin-Out. After a +1 Bug Buzz has a high damage output and is a clear one shot on Mega-Latias.


Calcs:

Hide

Mega Latias vs Volcarona
0 SpA Volcarona Flamethrower vs. 248 HP / 0 SpD Latias-Mega: 44-52 (12.1 - 14.3%) -- possible 7HKO after Stealth Rock
0 SpA Volcarona Bug Buzz vs. 248 HP / 0 SpD Latias-Mega: 176-210 (48.4 - 57.8%) -- guaranteed 2HKO after Stealth Rock
0 SpA Volcarona Savage Spin-Out (175 BP) vs. 248 HP / 0 SpD Latias-Mega: 342-404 (94.2 - 111.2%) -- guaranteed OHKO after Stealth Rock
+1 0 SpA Volcarona Bug Buzz vs. 248 HP / 0 SpD Latias-Mega: 266-314 (73.2 - 86.5%) -- guaranteed 2HKO after Stealth Rock
+1 0 SpA Volcarona Savage Spin-Out (175 BP) vs. 248 HP / 0 SpD Latias-Mega: 512-606 (141 - 166.9%) -- guaranteed OHKO

0 SpA Latias-Mega Stored Power (20 BP) vs. 248 HP / 0 SpD Volcarona: 28-34 (7.5 - 9.1%) -- possible 6HKO after Stealth Rock
0 SpA Latias-Mega Ice Beam vs. 248 HP / 0 SpD Volcarona: 42-49 (11.2 - 13.1%) -- 17% chance to 4HKO after Stealth Rock
+1 0 SpA Latias-Mega Stored Power (60 BP) vs. 248 HP / 0 SpD Volcarona: 126-148 (33.7 - 39.6%) -- guaranteed 2HKO after Stealth Rock
+1 0 SpA Latias-Mega Ice Beam vs. 248 HP / 0 SpD Volcarona: 62-73 (16.6 - 19.5%) -- 100% chance to 3HKO after Stealth Rock

Clefable vs Volcarona
0 SpA Volcarona Flamethrower vs. 80 HP / 0 SpD Clefable: 138-163 (39.3 - 46.4%) -- guaranteed 3HKO
0 SpA Volcarona Bug Buzz vs. 80 HP / 0 SpD Clefable: 69-81 (19.6 - 23%) -- possible 5HKO
+1 0 SpA Volcarona Flamethrower vs. 80 HP / 0 SpD Clefable: 205-243 (58.4 - 69.2%) -- guaranteed 2HKO
+1 0 SpA Volcarona Bug Buzz vs. 80 HP / 0 SpD Clefable: 102-121 (29 - 34.4%) -- 5.8% chance to 3HKO
+2 0 SpA Volcarona Flamethrower vs. 80 HP / 0 SpD Clefable: 274-324 (78 - 92.3%) -- guaranteed 2HKO
+2 0 SpA Volcarona Bug Buzz vs. 80 HP / 0 SpD Clefable: 137-162 (39 - 46.1%) -- guaranteed 3HKO
+2 0 SpA Volcarona Savage Spin-Out (175 BP) vs. 80 HP / 0 SpD Clefable: 266-313 (75.7 - 89.1%) -- guaranteed 2HKO

252+ SpA Life Orb Clefable Moonblast vs. 248 HP / 0 SpD Volcarona: 86-101 (23 - 27%) -- 43.8% chance to 2HKO after Stealth Rock
252+ SpA Life Orb Clefable Fire Blast vs. 248 HP / 0 SpD Volcarona: 133-157 (35.6 - 42%) -- guaranteed 2HKO after Stealth Rock
252+ SpA Life Orb Clefable Thunderbolt vs. 248 HP / 0 SpD Volcarona: 109-129 (29.2 - 34.5%) -- guaranteed 2HKO after Stealth Rock
252+ SpA Life Orb Clefable Moonblast vs. +1 248 HP / 0 SpD Volcarona: 57-68 (15.2 - 18.2%) -- 47.5% chance to 3HKO after Stealth Rock
252+ SpA Life Orb Clefable Fire Blast vs. +1 248 HP / 0 SpD Volcarona: 88-105 (23.5 - 28.1%) -- 82.8% chance to 2HKO after Stealth Rock
252+ SpA Life Orb Clefable Thunderbolt vs. +1 248 HP / 0 SpD Volcarona: 73-86 (19.5 - 23%) -- guaranteed 3HKO after Stealth Rock

​

 

[Stall is coming]

I believe that Reuniclus was a good threat, it is not :(

Reuniclus @ Leftovers
Ability: Magic Guard
EVs: 248 HP / 136 Def / 80 SpD / 44 Spe
Bold Nature
- Calm Mind
- Acid Armor
- Psyshock
- Recover

Reuniclus is incredible in the metagame at the moment (maybe OU soon). I use the optional spread of Smogon to avoid being 2HKOed by Moonblast and Thunderbolt from Mega Diancie and Tapu Koko.

Calcs:

252+ SpA Life Orb Clefable Moonblast vs. 252 HP / 80 SpD Reuniclus: 187-220 (44.1 - 51.8%) -- guaranteed 3HKO after Leftovers recovery

+1 0 SpA Latias-Mega Ice Beam vs. 248 HP / 80 SpD Reuniclus: 136-160 (32.1 - 37.8%) -- 0.3% chance to 3HKO after Leftovers recovery
+2 0 SpA Latias-Mega Ice Beam vs. +1 248 HP / 80 SpD Reuniclus: 120-142 (28.3 - 33.5%) -- 95.9% chance to 4HKO after Leftovers recovery
+3 0 SpA Latias-Mega Stored Power (140 BP) vs. +2 248 HP / 80 SpD Reuniclus: 131-155 (30.9 - 36.6%) -- guaranteed 4HKO after Leftovers recovery
+4 0 SpA Latias-Mega Stored Power (180 BP) vs. +3 248 HP / 80 SpD Reuniclus: 162-191 (38.2 - 45.1%) -- guaranteed 3HKO after Leftovers recovery
+5 0 SpA Latias-Mega Stored Power (220 BP) vs. +4 248 HP / 80 SpD Reuniclus: 192-227 (45.3 - 53.6%) -- 2% chance to 2HKO after Leftovers recovery
+6 0 SpA Latias-Mega Stored Power (260 BP) vs. +5 248 HP / 80 SpD Reuniclus: 222-262 (52.4 - 61.9%) -- 98.8% chance to 2HKO after Leftovers recovery
+6 0 SpA Latias-Mega Stored Power (260 BP) vs. +6 248 HP / 80 SpD Reuniclus: 195-230 (46 - 54.3%) -- 5.9% chance to 2HKO after Leftovers recovery
+6 0 SpA Reuniclus Psyshock vs. 252 HP / 4 Def Latias-Mega: 177-209 (48.6 - 57.4%) -- 94.1% chance to 2HKO

Like you see, Reuniclus is a counter to both pokemons (even psyshock Latias ...).

De Blob @ Eviolite
Ability: Natural Cure
EVs: 248 HP / 252 Def / 8 SpD
Bold Nature
- Seismic Toss
- Toxic
- Stealth Rock
- Soft-Boiled

Pitiful damage

252+ SpA Life Orb Clefable Moonblast vs. 248 HP / 8 SpD Eviolite Chansey: 114-136 (16.2 - 19.3%) -- possible 6HKO
+1 0 SpA Latias-Mega Stored Power (60 BP) vs. 248 HP / 8 SpD Eviolite Chansey: 84-99 (11.9 - 14%) -- possible 8HKO
+3 0 SpA Latias-Mega Stored Power (140 BP) vs. 248 HP / 8 SpD Eviolite Chansey: 319-376 (45.3 - 53.4%) -- 36.3% chance to 2HKO

Chansey can pose SR against Clefable freely. Thanks to toxic, LatiasM can't setup against Chansey. Moreover, this set of Clefable doesn't have leftovers, so it doesn't like seismic toss spam.
So, Chansey is a counter to both.

 

[superstrike66]

reserving Kyurem-Black

 

[VCrakeV]

Going to make a submission, but first a note on Sableye-mega. I don't think that not being a counter to Koko is a sufficient reason to say max defense Sableye is a bad set for the current meta. Firstly, SpD sets can't counter Koko either; they are 2HKOed by specs dazzling gleam and wild charge sets (the latter of which physically defensive sets avoid the 2HKO from, though one must be wary of the z move). Additionally, Sableye is almost always paired with Chansey, which can check the special sets physically defensive Sableye struggles with. Sableye is also not forced out by Koko if it gets a cm boost (bar specs dazzling gleam).

Anyway, let's check Clefable with Clefable:

Clefable @ Leftovers
Ability: Unaware
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
IVs: 0 Atk
- Wish
- Protect
- Moonblast
- Calm Mind

Defensive Clefable almost always avoids the 2HKO from LO Clefable's moonblast; you can also move some defense EVs to SpD while still checking Mega Lopunny and Hawlucha. Calm mind allows Clefable to more easily wall Clefable, and effectively negates the high base power of stored power. Unaware negates Latias' special attack boosts, and also ignores defensive boosts, so you can easily win the cm war.

 

[Deleted User [433215]]

Going to make a submission, but first a note on Sableye-mega. I don't think that not being a counter to Koko is a sufficient reason to say max defense Sableye is a bad set for the current meta. Firstly, SpD sets can't counter Koko either; they are 2HKOed by specs dazzling gleam and wild charge sets (the latter of which physically defensive sets avoid the 2HKO from, though one must be wary of the z move). Additionally, Sableye is almost always paired with Chansey, which can check the special sets physically defensive Sableye struggles with. Sableye is also not forced out by Koko if it gets a cm boost (bar specs dazzling gleam).

Anyway, let's check Clefable with Clefable:

Clefable @ Leftovers
Ability: Unaware
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
IVs: 0 Atk
- Wish
- Protect
- Moonblast
- Calm Mind

Defensive Clefable almost always avoids the 2HKO from LO Clefable's moonblast; you can also move some defense EVs to SpD while still checking Mega Lopunny and Hawlucha. Calm mind allows Clefable to more easily wall Clefable, and effectively negates the high base power of stored power. Unaware negates Latias' special attack boosts, and also ignores defensive boosts, so you can easily win the cm war.

A threat to this core is both Jirachi varients, being Scarf and the utility sets, the Scarf set being a harder matchup.

Jirachi @ Choice Scarf
Ability: Serene Grace
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Iron Head
- U-turn
- Healing Wish
- Fire Punch

Jirachi @ Leftovers
Ability: Serene Grace
EVs: 248 HP / 188 SpD / 72 Spe
Careful Nature
- Wish
- Protect
- Iron Head
- Body Slam

The Scarf set outspeeds both Latias and Clefable and can flinch both of them down, especially since Latias can’t even touch Jirachi. The SpDef set meanwhile has the longevity to play the long game thanks to Wish and the improved bulk, although this set can only win if its Body Slam since Latias naturally outspeeds otherwise and just Calm Minds up. It should be noted while neither set switches into Clefable’s Fire Blast, the Scarf set can take one from full and the SpDef set only takes at max 62%, so it can recover it all back if it gets an opportunity to wish.

 

[VCrakeV]

Stored Power’s base power increase means you still lose the cm war

You ignore its SpA boosts because of unaware though, so its SpA effectively does not go up as your SpD goes up:

+6 0 SpA Latias-Mega Stored Power (260 BP) vs. +6 252 HP / 4 SpD Unaware Clefable: 102-121 (25.8 - 30.7%) -- 4.3% chance to 4HKO after Leftovers recovery

 

[JCVD is forever]

reserving z-move heatran

 

[Solaros & Lunaris]

Charizard @ Charizardite X
Ability: Blaze
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Dragon Dance
- Flare Blitz
- Dragon Clsw
- Roost

Easily 1v1s Mega Latias thanks to Dragon Claw. LO Clef is a bit harder though. Flare Blitz is not a guarenteed OHKO but its a roll in your favor. If you’re feeling hard pressed against Clef, you eat Moonblast to DD and kill with Flare Blitz, though this will probably compromise a ZardX sweep. Also we have mini sprites now

 

[Sayuze]

Alakazam @ Alakazite
Ability: Magic Guard
EVs: 252 SpA / 4 SpD / 252 Spe
Modest Nature
IVs: 0 Atk
- Psychic
- Focus Blast
- Shadow Ball
- Recover

So recently I actually tried building teams in particular to have a good matchup vs. the latias-clef balances that Lopunny Kicks / Ben gay had made (the z rotom and z gunkshot gren ones) as well as after losing to Liones a few times on ladder to his Pex-Steela-Ditto matchup bullshit, I was inspired to build with something that had a good matchup vs. that as well.

What I came up with was Modest Zam. I know this is obv not a new invention, but it pretty much destroys those teams as they don't have too reliable switch ins. The combo of Psychic/Shadow ball/Focus blast works (70% of the time kek, jk) to dismantle the core. The Rotom/Clef/Latias team gets popped by Modest Zam as its initial answer is SpDef Clef which will get 2hko'd almost always. As for the Ben gay team with Z Gunk shot gren, it has even more of a good matchup vs that, just watch out for T-Wave Latias. Magnezone is something I also run with modest zam as it heavily easens the Ferrothorn/Celesteela matchup that Zam faces.

Also, Stall is coming from experience Reuniclus has trouble beating the core but it definitely can with the right support or timing. U calc'd vs regular latias and not mega latias which would give you a pretty big difference :p

Just something to add, the core of T-wave CM Clef + CM Stored Power Latias is really potent and one of the best cores in this gen for sure. It can really beat pretty much anything if you play well or have the right luck... But I think Modest Zam comes pretty close to being able to reliably beat them

 

[Stall is coming]

Also, Stall is coming from experience Reuniclus has trouble beating the core but it definitely can with the right support or timing. U calc'd vs regular latias and not mega latias which would give you a pretty big difference :p

Well

 

[JinLong88]

Diancie @ Diancite
Ability: Clear Body
EVs: 252 SpA / 4 SpD / 252 Spe
Hasty Nature
- Stealth Rock
- Moonblast
- Diamond Storm
- Earth Power

This pink precious-stoned princess is the paragon of a wallbreaker that checks the core of Mega-Latias + LO clefable.

Her good speed threatens potential z-users like z-kart, z-chomp, or z-blace, if the core is used on a balance/BO build.

If she gets in freely vs them, Moonblast 2hko clef, while 75% chance to 2hko +1 spDef mega-lat (provided she wins the speed tie).
Moonblast's 30% chance to drop spAtk would away their offensive power, as well as lowering stored power's BP.

Magic Bounce is not helpful vs their sets, though it'd be a boon if clef decided to run t-wave. And obviously Bounce can help prevent hazards and keep Diancie's teammates away from KO ranges of the core's sets.

Mega-Diancie is a good SR-setter since she pressures common defoggers that would join the core including torn, zap, rotom-w, and defensive lando. SR would of course assist her teammates in wearing down mega-lat.

Diamond Storm not only threatens torn+zap but helps significantly break down chansey, which may be found with the core to answer things like 'rona, protect+SR tran, and the zam set above.

Lastly, Earth Power and its drop chance can chunk out the HPs of:
- pex (which provides gren switchin and tspikes),
- rachi, mage (which checks psyspam for this core) and
- spdef tran (which when healthy is a second check to offensive tran after mega lat)

The downsides of her are many, including her common type weaknesses, her 4mss and hp-fire the only way to threaten ferro, susceptibility to priority, and just overall fragility.
Still I find this Ms. Bling to be an interesting choice that offensively checks/pressures this core and its common teammates.

P.S. I've been mostly a lurker over these years and this is part of my attempt to hopefully contribute more than I've done in the past