First time submitting a core to this thread. I'd like to share this offensive core of mine that has shown me a lot of success this generation. I haven't seen this specific trio featured here yet all together (unless I missed it further up the thread), so I figured I'd throw it in along with some of my own insight.
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Modest Specs Tapu Lele + SD Garchomp + Volcarona
Raw paste link:
https://pokepast.es/b83a0927c97d965d
Explanation:
This offense scheme is a great way to overwhelm common checks and aim for late game sweeps. It's a very brute force approach, but has smart ways of achieving its power.
Tapu Lele and Garchomp can overpower shared checks such as Corviknight over time, and Modest Choice Specs Tapu Lele in particular can even 2HKO the common Defog Corviknight with a bit of prior damage, especially if it doesn't have Leftovers due to allied Knock Off or preferring Rocky Helmet, since Corviknight is one of Garchomp's most annoying adversaries. Tapu Lele and Garchomp also do a good job of overpowering Ferrothorn, as Tapu Lele can lure it in while it stays away from Volcarona enough for Garchomp to set up on it and kill it in one hit after enough battering, thanks to Ferrothorn's lack of true hard recovery. Volcarona can sometimes miss an OHKO or be afraid to Quiver Dance when a healthy Corviknight uses Brave Bird; this way Volcarona can just click Flamethrower and kill if the situation calls for it via Tapu Lele weakening it enough. In some instances, Garchomp can set up Swords Dance enough (depending on the opposing Corviknight spread) to gamble a 2HKO with Stone Edge's poor accuracy; an option which is less desirable because of low PP + Pressure stall and sees viability as a last ditch effort in most cases. Choice Specs Tapu Lele can also 2HKO Melmetal in many situations, especially more offensive variants. This Tapu Lele can also OHKO common Defensive Landorus-T with much more consistency than its Timid counterpart to eliminate counterplay for Garchomp.
Garchomp in particular helps the other two by actively being one of the best Heatran checks in the game. Tapu Lele can gamble a Focus Blast vs a Heatran with prior damage and kill it, but Garchomp serves as insurance. Garchomp and Tapu Lele together do a good job of ridding Heatran from the opposing team, which Volcarona loves, among other things as well such as handling Galarian Slowking via use of Psyshock + Earthquake, forcing it in enough, eliminating another annoying mon for Volcarona so that it doesn't have to worry too much about Sludge Bomb hax gimping its longevity over time as it sets up. I generally like Fire Fang on Garchomp for the sake of overpowering its own checks such as Corviknight and even Buzzwole in certain situations, if you have to, but Stone Edge can be opted for if you need to remove things like Zapdos and Tornadus-T quickly, if the team calls for the classic Edge/Quake combo. Usually, Fire Fang is the best choice here.
The bulky Volcarona set serves as a check to a lot of common switch ins to both Garchomp and Tapu Lele in itself, punishing Grassy Glide from Rillaboom and Double Iron Bash from Melmetal, respectively, with Flame Body's burn chance. This one is only barely different from the one currently posted in the Smogon article, only adjusted to outspeed base 80 Speed opponents that show up sometimes, such as the occasional Choice Scarf Mamoswine that knows Volcarona is the bulky spread and attempts to revenge kill after a Quiver Dance, for example. Volcarona also helps against Kartana, which can provide free setup for Volcarona to sweep in many cases and is a menace to the other two mons in the core across its possible sets, provided it has not set up a prior Swords Dance ahead of time. Another mon that Garchomp dislikes is Buzzwole, which Volcarona punishes quite well, and Tapu Lele outright beats offensively. This Volcarona also functions well as a Kyurem answer, something which is in short supply in today's metagame, thus making it even more valuable especially given that Kyurem runs Draco Meteor a lot less these days than it has in the past.
Teambuilding considerations:
Stealth Rock is obviously really important to ensure this core's success, as seen in the calcs below. This core also appreciates mons that can bring them in safely, especially Teleport users such as Rocky Helmet Slowbro, who likes to run Ice Beam to relieve pressure from opposing offensive Garchomp and Landorus-T, two mons that can take advantage of the core and set up/sweep. Slowbro in particular really alleviates pressure off of Volcarona to check Choice Band Melmetal, who can 2HKO Volcarona if Flame Body does not activate and is healthy enough to have a chance to survive Flamethrower in return. The core also appreciates solid answers to Dragapult, which can give these three a lot of trouble by either spamming Shadow Ball with the Choice Specs set or setting up on Volcarona with the Dragon Dance set; one such mon I've used to help vs Dragapult is an allied Mandibuzz kept healthy enough to force it out or kill. Blacephalon can also be a massive problem for this core, especially if holding Choice Specs. Crawdaunt, when it shows up, is also difficult to manage, but Tapu Lele offers some counterplay against it via Psychic Terrain, provided the player is wise about bringing Tapu Lele in at the right time vs Crawdaunt. One more massive threat to this core is Weavile, which usually has to be played around smartly. Volcarona's spread has a small chance to live vs Swords Dance Weavile's Knock Off, enabling a kill in return, so this helps a little bit, making the spread important in a last ditch effort. Buzzwole helps to answer opposing Weavile well, and is a consideration as a team partner to this core, while still handling offensive Landorus-T and Garchomp as the aforementioned Slowbro would.
Relevant damage calcs:
252+ SpA Choice Specs Tapu Lele Psychic vs. 248 HP / 92 SpD Corviknight in Psychic Terrain: 162-191 (40.6 - 47.8%) -- 59% chance to 2HKO after Stealth Rock
252+ SpA Choice Specs Tapu Lele Psychic vs. 40 HP / 104 SpD Melmetal in Psychic Terrain: 193-228 (45.8 - 54.1%) -- 96.1% chance to 2HKO after Stealth Rock
+2 252 Atk Garchomp Stone Edge vs. 248 HP / 4 Def Corviknight: 209-246 (52.3 - 61.6%) -- 98.4% chance to 2HKO after Leftovers recovery
+4 252 Atk Garchomp Stone Edge vs. 248 HP / 168+ Def Corviknight: 244-288 (61.1 - 72.1%) -- guaranteed 2HKO after Stealth Rock and Leftovers recovery
+2 252 Atk Garchomp Fire Fang vs. 248 HP / 168+ Def Corviknight: 214-252 (53.6 - 63.1%) -- guaranteed 2HKO after Leftovers recovery
+2 252 Atk Garchomp Earthquake vs. 252 HP / 4 Def Ferrothorn: 258-304 (73.2 - 86.3%) -- guaranteed 2HKO after Leftovers recovery
+2 252 Atk Garchomp Earthquake vs. 252 HP / 252+ Def Ferrothorn: 195-229 (55.3 - 65%) -- guaranteed 2HKO after Leftovers recovery
252+ SpA Choice Specs Tapu Lele Psychic vs. 252 HP / 0 SpD Landorus-Therian in Psychic Terrain: 379-447 (99.2 - 117%) -- 93.8% chance to OHKO
252+ Atk Choice Band Iron Fist Melmetal Double Iron Bash (2 hits) vs. 248 HP / 148 Def Volcarona: 240-284 (64.3 - 76.1%) -- approx. 2HKO
252+ SpA Choice Specs Tapu Lele Psychic vs. 252 HP / 56+ SpD Clefable in Psychic Terrain: 294-346 (74.6 - 87.8%) -- guaranteed 2HKO after Leftovers recovery
252+ SpA Choice Specs Tapu Lele Psychic vs. 252 HP / 4 SpD Clefable in Psychic Terrain: 342-403 (86.8 - 102.2%) -- 18.8% chance to OHKO
252+ SpA Choice Specs Tapu Lele Psyshock vs. 252 HP / 12 Def Slowking-Galar in Psychic Terrain: 331-391 (84 - 99.2%) -- guaranteed 2HKO
16 SpA Volcarona Flamethrower vs. 252 HP / 0 SpD Buzzwole: 422-500 (100.9 - 119.6%) -- guaranteed OHKO
+2 252 Atk Weavile Knock Off (97.5 BP) vs. 248 HP / 148 Def Volcarona: 348-411 (93.2 - 110.1%) -- 62.5% chance to OHKO
I hope this was insightful enough, and that someone out there can enjoy this as much as I have!
UPDATE: NEXT CORE
Hello once again! I enjoyed doing my first core analysis so much that I decided to do another one. This is a
defensive core that I haven't seen on here at all yet, with two mons that nonetheless keep showing up in this thread as parts of other cores. I've been loving this core a lot recently due to its ability to compliment the rest of its team and mesh well with a wide array of builds. Click the images for the paste.
Rotom-Wash + Galarian Slowking
Explanation:
This core has a very effective synergy to it; it handles most things and is adaptable to the team around it. It's a defensive core that isn't passive and gives you a few different options for what your team may need from it. For this reason, I almost called it a balanced core, but defensive is still the most apt description.
Physically defensive Rotom-Wash is a quite underrated mon in today's metagame, despite being one of the most storied threats throughout previous OU metagames. It's a great check to a huge number of opposing physical threats with its own ways of punishing them. It handles things like lead Landorus-T and its offensive variants as well, along with Garchomp and things like Melmetal via resists and especially gimping them long-term with Will-O-Wisp. Rotom-Wash also serves as a great check to Scizor thanks to the given speed investment creeping up above Scizor's Adamant 252 Speed variants. It can even take on super overwhelming offensive waters you'll encounter such as Urshifu-RS and Barraskewda, especially if Pain Split is chosen or if played wisely. If kept healthy, Rotom-Wash beats Hawlucha, even surviving +2 Close Combat and killing in return with Volt Switch, providing momentum in the same turn, since Close Combat is Hawlucha's only situational chance of beating Rotom-Wash. Rotom-Wash often ends up being the Defogger of choice on the team, so Pain Split ends up becoming the first choice in what to scrap in favor of hazard removal, since it can still be plenty effective this way if you're careful with budgeting its HP and evaluating its role in any given matchup, especially on offense builds.
Galarian Slowking appreciates all of these things that Rotom-Wash beats and handles a great number of things that it struggles against. Galarian Slowking can lead the way in beating Kyurem with the help of its teammates, and provides ample counterplay to powerful threats such as Tapu Koko, Calm Mind + Draining Kiss Tapu Fini, and Magnezone. Future Sight is a way that Galarian Slowking supports more offensive members of its team that can be built outside of this core, but if this move isn't required due to lack of Future Sight abusers, Psychic is a great option to have more immediate Psychic STAB vs things like Toxapex who commonly assume they have a few turns to cause trouble for you, or against mons who are choice locked into fighting type moves, hilariously struggling to damage the physically frail Galarian Slowking despite all that physical power, thanks to its double resist typing. It's worthy to note that this spread will always survive against Jolly Choice Band Surging Strikes from full health (provided there is no rain) and OHKO in return with Psychic. This is another good reason to consider Psychic over Future Sight if you have no need for Future Sight on your team; this helps Rotom-Wash to keep from being overwhelmed by opposing physical threats, especially if it opts out of Pain Split. Shoutout to whoever came up with the current sample spread on Galarian Slowking's strategy dex article where I got it from; that's great thinking. Another cool tech I've seen on Galarian Slowking before is Eerie Spell, but this is generally less effective in the long run due to its own low PP. If your team ends up lacking a hard Heatran check, the last move slot can be Earthquake. If this is opted for, run a Sassy nature and 31 Attack IVs. It is always advisable to run another Heatran check, however, as Galarian Slowking only barely wins on the switch in vs Magma Storm + Earth Power SpDef Heatran, and can lose quite often as well; reasons why it should only be used as a Heatran check if you absolutely need to use it that way.
Teambuilding considerations:
There are few things that this core is weak to that are easily patched up by the rest of its team. For example, Tapu Lele can spam Psyshock on it and beat it quite easily, so a solid answer to Tapu Lele is paramount. A good steel type works well. Corviknight is one such example, since it can handle most variants of Tapu Lele and also defeat Mold Breaker Excadrill and Kartana, both of which this core hard loses to on its own. Bisharp is a noteworthy partner for this core to cross check Tapu Lele alongside Galarian Slowking, as it also helps against threats such as Weavile lacking Low Kick, and alleviates pressure from typical Ghost spam dished out by mons like Choice Specs Dragapult. Additionally, a form of speed control is advisable on balance and offense teams that utilize this core, as some of the faster mons in the tier, when paired together, can overwhelm. Common choice scarf users such as Tapu Lele, Kartana, and even Choice Scarfed Kyurem are good options to achieve this goal. Since Galarian Slowking loves to use Future Sight, and Rotom-Wash is a fantastic Volt Switch user, both can support setup mons such as Garchomp, Swords Dance Weavile, Dragonite, Dragon Dance Dragapult, and Volcarona who appreciate what this core can do otherwise, especially if paired with the aforementioned speed control. Blacephalon can be tricky to play against, since it's usually choiced, making its counterplay prediction reliant and it can use trick to disrupt the core. Urshifu-RS can overwhelm and easily 2HKO Rotom-Wash while rain is active, so a plan to whittle it down and keep Rotom-Wash healthy in this scenario is of utmost importance, since Volt Switch doesn't OHKO from full. Catching it with a Will-O-Wisp if you can effectively do so helps with this situation quite a lot, obviously. All of these things are points to consider when building counterplay for the tier alongside this core.
Relevant damage calcs:
+2 252+ Atk Hawlucha Close Combat vs. 252 HP / 168+ Def Rotom-Wash: 250-295 (82.2 - 97%) -- guaranteed 2HKO after Leftovers recovery
0 SpA Rotom-Wash Volt Switch vs. -1 0 HP / 132 SpD Hawlucha: 288-338 (96.9 - 113.8%) -- 75% chance to OHKO
252+ Atk Choice Band Iron Fist Melmetal Double Iron Bash (2 hits) vs. 252 HP / 168+ Def Rotom-Wash: 76-90 (25 - 29.6%) -- approx. 5HKO after Leftovers recovery
252 Atk Choice Band Urshifu-Rapid-Strike Surging Strikes (3 hits) vs. 252 HP / 12 Def Slowking-Galar on a critical hit: 327-390 (82.9 - 98.9%) -- approx. 2HKO
124 SpA Slowking-Galar Psychic vs. 0 HP / 0 SpD Urshifu-Rapid-Strike: 356-422 (104.3 - 123.7%) -- guaranteed OHKO
252+ SpA Choice Specs Kyurem Ice Beam vs. 252 HP / 176+ SpD Assault Vest Slowking-Galar: 117-138 (29.6 - 35%) -- 13.4% chance to 3HKO
0 SpA Rotom-Wash Volt Switch vs. 0 HP / 0 SpD Barraskewda: 272-324 (103.4 - 123.1%) -- guaranteed OHKO
252+ Atk Choice Band Barraskewda Liquidation vs. 252 HP / 168+ Def Rotom-Wash in Rain: 122-144 (40.1 - 47.3%) -- guaranteed 3HKO after Leftovers recovery
0 SpA Rotom-Wash Volt Switch vs. 0 HP / 0 SpD Urshifu-Rapid-Strike: 236-282 (69.2 - 82.6%) -- guaranteed 2HKO
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CM variants of Clef can cause major problems to this core as CM Clef can carry flamethrower and thus can dumpster ferro after a boost.Using iron head on Ferro can help with this mu but it will still be quite a difficult one.
Volc is kind of impossible for this core to deal with on it’s own as it can freely come in on ferro and grab a qd while also being able to eat a dragapult draco If it needs to.
Heatran can be a problem for these two so paring them with a heatran swap in is key but heatran can be overpressured by dragapult offensively especially when spikes are on the field which can help vs it.
Kart can be a very problematic mon to this core as it can threaten out pult if it’s scarf if not it can limit swap in opportunities into pult by pressuring the team with offense. Both of the mons in the core can’t switch in on it safely as it can fire off powerful knock offs and sacred swords on the switch which both pult and ferro fear
Zone teams can be a problem for these two as zone can trap ferro and let their team’s offensive threats which are walled by Ferro go ham on the rest of the team.
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/ Chople Berry 
, Blissey 
, Clefable 
, Corviknight 
, and Ferrothorn 
and Kartana 
, and Hippowdon 
. Landorus and Garchomp can be overwhelmed gradually through the use of Toxic, hazards, and chip such as Magma Storm from Heatran or the optional Flash Cannon from Magnezone. Hippowdon can be difficult to wear down throughout a match as it has consistent recovery from Slack Off, however, Heatran can switch into it consistently so long as its Air Balloon is not popped.
. While the former of the two is primarily intended to remove Aegislash alongside the latter, due to its limited recovery switching can be risky as Heatran cannot come in on Aegislash more than once or twice due to its high power STABs and Close Combat. Against Aegislash, it is important to preserve offensive momentum and scout its set so as to avoid unnecessary risks and tradeoffs.
, Tornadus 
, and Volcarona 
Threats: 
prove to be an uneasy adversary for Heatran and Magnezone. It is immune to Earth Power and resists Heatran and Magnezone's STABs. Moreover, Dragonite turns both into setup fodder with its coverage and bulk. It commonly utilizes Heavy-Duty Boots to preserve its Multiscale, which when paired with its access to Roost makes it difficult to chip.
, Quagsire 
, Seismitoad 
, and Swampert 
all present their unique issues for Heatran and Magnezone. Gastrodon and Quagsire are the most threatening of the 4, having access to consistent recovery and dual resistances / type effectiveness. Seismitoad and Swampert pose the same threat, where both trade recovery for hazards, and unlike the former, Swampert receives Flip Turn.
, Weavile 
, and Dragonite 
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