Fantastic Cores and How to Beat Them


By Tangent444, NHoff, Gastonagustin, Nesabethan and PolymersUp


Ultra League (UL) is back in GO Battle League (GBL) Season 3 and so are we—ready to break down a few top GBL meta cores. We’ve had several changes since UL was the only GBL show in town: Gengar and Gyarados Community Days; the ascent of Abomasnow and Drifblim into relevance; Registeel and Cresselia nerfs; and two Shadow events to open up more possibilities. So let’s get to it!


What is a Core?


A Core is a pair of Pokémon that synergize well together, and trio cores are composed of multiple powerful duos. Therefore, any single Pokémon in the trio core can often be substituted for another partially complementary Pokémon to create a solid line that’s less predictable. Core breakers are Pokémon that generally perform well, even in a loss, against all members of a duo or trio core. You might only face two of the three shown in any given battle, but bringing one of these core breakers means you’ll be well positioned no matter which of those duos you see.


How does the Graphic work?


Each GBL meta-defining trio core is surrounded by six core breakers. Each segment of the encircling ring reflects its matchup with the respective trio core Pokémon. A Win (dark teal) or Loss (dark purple) generally indicates the outcome in even-shield scenarios, and these matchups are less likely to flip due to slight energy differentials. Even (grey), Narrow Win (light teal) and Narrow Loss (light purple) reflect which way the matchup generally trends and implies that IVs and slight energy differentials might play a larger role in the outcome. Importantly, Pokémon walled by one of the three (e.g. Meganium against Altaria or Tropius) were not considered despite having solid matchups against two of the three. As these trios are composed of multiple strong duos, sometimes one of three Pokémon are replaced with another pick to reduce predictability or better counter the current meta. We limited the graphics to 6 of the top core breakers but there are of course other solid options, some of which are highlighted in the Alternatives sections. Try integrating these core breakers into your lineup to counter some of the top cores in GBL.



— Terms —



Note that 0/1/2S refers to the even-shield scenarios in simulations from All wins or losses mentioned are even-shield scenarios with zero starting energy unless otherwise stated. Stat Product (SP) and IVs are occasionally referenced. Exclusive moves (^(E)) cannot be acquired by regular TMs and are either legacy or obtained through previous events, purification or use of an Elite TM.


— Giratina Altered + Registeel + Swampert —


Ultra League is known for the dominant presence of a few Legendary Pokémon, and that conversation often starts with Giratina Altered and Registeel. What this core lacks in excitement and creativity is made up for by its ability to cover the meta incredibly well. Along with Swampert, another mainstay of the UL meta, this core represents some of the most common threats paired together set out to prove they deserve the title of meta kingpins.


Giratina Altered Dragon Breath + Dragon Claw + Shadow Sneak


While Shadow Claw has its own merits, this core best functions with Dragon Breath Giratina due to its ability to improve its matchups with Obstagoon, Snorlax, Shiftry, and Swampert, all of which the other core members appreciate being dealt with. This leaves Giratina more vulnerable to opposing Steel and Psychic type Pokemon, but that’s where Registeel and Swampert pick up the slack. Dragon Breath also makes matters worse against Charm users, but those were already bad to begin with and Registeel is on the team to help out if Giratina gets trapped by a Charmer.


Registeel Lock-On + Flash Cannon + Focus Blast


Registeel is an ideal partner for Giratina Altered. Registeel covers Charm users, Ice types, and Cresselia that threaten Giratina, and in return Giratina provides Registeel with protection from Counter users, Fire types, and Swampert. The nerfs to Flash Cannon and Focus Blast may hurt Registeel’s usage, but overall its contribution to this core remains as strong as ever.


Swampert Mud Shot + Hydro Cannon + Earthquake


Swampert appreciates Registeel and Giratina tag teaming to take out any Grass type daring enough to wander around in the Ultra League Meta. In return, Giratina appreciates Swampert’s ability to handle opposing Registeel and Clefable, while Registeel appreciates Swampert taking care of Charizard and going even with opposing Swampert. And while Swampert losing to Articuno and Togekiss might feel like it doesn’t pair well with Giratina losing those matchups hard, Registeel is there to wall any momentum they might create.


It is worth noting that Cresselia + Registeel makes roughly as good of a core duo as Giratina + Registeel, handling Charm and Ice much better but struggling more with Fire and Escavalier. We chose to highlight Giratina + Registeel, but acknowledge that Cresselia + Registeel can be equally dominant when paired with Swampert.




Gyarados Dragon Breath + Aqua Tail + Crunch


Gyarados is a prime candidate as a core breaker, as it has slightly positive matchups with all three members of the core. While it will not win any of these matchups hard, it can win enough to help set-up switch advantage which could put a Charm user against Giratina or Swampert against Registeel. Gyarados is most vulnerable to Dragon Breath Giratina, typically losing 0S and 2S. However, a very high defense weighted Gyarados has a chance to secure a more comfortable win if it picks up a Dragon breath bulk point (minimum of 141.34 defense is required, but cannot be guaranteed).


Drifblim Hex + Icy Wind + Shadow Ball


Drifblim is more of a newcomer to the Ultra League Meta, but the buff to Hex has launched it onto the scene. With straight Icy Wind, it beats Dragon Breath Giratina in 1S and 2S and barely loses 0S, and can win 0S by landing a Shadow Ball + Icy Wind. Against Swampert, Drifblim wins in 1S and 2S with straight Icy Wind, and wins 0S by landing a Shadow Ball + Icy Wind. Against Registeel, Drifblim wins 0S and 2S with straight Shadow Ball, and can win the 1S if Registeel uses a shield on an Icy Wind instead of a Shadow Ball (Drifblim needs to shield one of the first two Flash Cannons to pull this off). Overall, it’s positioned well against all three members of the core.


Poliwrath Mud Shot + Ice Punch + Dynamic Punch


Poliwrath plays similar to Swampert in some respects, but is a marginally stronger pick for breaking this core. Poliwrath is a hard answer to Registeel, is generally positive against Swampert (though it can lose some scenarios with Swampert depending on shield baiting on each side), and loses close to Giratina in the 0S scenario. Poliwrath will provide some value no matter which core member it is faced with, but getting Registeel locked-in could be enough to win the game. In comparison, Swampert tends to lose harder to Dragon Breath Giratina.


Escavalier Counter + Drill Run + Megahorn


Escavalier is a similar core breaker to Poliwrath, as it counters Registeel hard, plays evenly with Swampert, and has a fairly close loss to Dragon Breath Giratina in the 0S and 1S scenarios. If Escavalier locks-in with Registeel, it can create a lot of momentum for its team by threatening Swampert or Giratina when they come in next with neutral charge moves (Drill Run only for Giratina, as Megahorn is resisted).


Meganium Vine Whip + Frenzy Plant + Earthquake


Grass is the hardest counter to Swampert in Ultra League, and Meganium is positioned as one of the strongest Grass types for the job of cracking this core. Its typing and bulk allow it to wall Swampert, due to Swampert typically running Earthquake in Ultra League instead of Sludge Wave. Additionally, the nerf to Flash Cannon allows Meganium just enough time to now have a bait-dependent win against Registeel in 1S and 2S scenarios, although it loses 0S if Registeel goes for double Focus Blast. However, Registeel users tend to go for double Flash Cannon unaware that Focus Blast is better when shields are down and end up losing a 0S matchup they could have won. As for Giratina, that is not a matchup Meganium can win, but the loss is very close in 0S and Meganium can simply elect not to shield in the matchup and leave Giratina with around 16HP or force it to burn a shield.


Other Grass types which can threaten this core include Sceptile and Shiftry. Sceptile gets shredded more by Giratina than Meganium does. Shiftry struggles more with Registeel than Meganium does, but can win 0S against Giratina and is a good option to consider as a core breaker.


Regice Lock-On + Earthquake + Blizzard


Want something unique to threaten this core? How about Regice! Did you know that Regice wins all even shield scenarios with Registeel? That’s thanks to Regice’s Earthquake. The nerf to Flash Cannon also makes the battle more comfortable for Regice as long as Registeel does not have a big enough energy advantage to outspeed it (4 Lock-Ons is enough to win 1S, but 6 Lock-Ons are needed to win 2S). Regice wins against Giratina in 0S and 1S, but does fall in 2S (leaving Giratina with roughly 11HP). Regice loses most even-shield scenarios with Swampert, but the 1S and 2S loses are by no means a blowout as long as it lands a Blizzard, and it can win the 0S scenario with two Earthquakes (though Swampert is one Mud Shot of energy away from flipping the 0S loss into a win).




Obstagoon threatens each individual core member with winning shield scenarios. It has an IV-dependent 0S win against DB Giratina, wins 2S against Registeel (as well as 1-0, and 2-1 shield advantage scenarios), and has an IV-dependent win against Swampert in all even-shield scenarios. Add in potential Night Slash boosts, and Obstagoon can be a tough Pokemon for the core to take out. However, Obstagoon gets one shot by Focus Blast and loses the 0S and 1S scenarios to Registeel, and loses handily to DB Giratina in 1S and 2S.


Giratina Altered goes nearly even with each of the three core members. Running Shadow Claw improves the Registeel matchup, while running Dragon Breath improves the Swampert matchup. SC Giratina ties with DC Giratina in 1S, but loses 0S and 2S. On a similar note, Giratina Origin defeats Registeel with straight Shadow Ball in all even-shield scenarios. However, it is one lock-on of energy away from having that matchup flipped. Giratina Origin has bait-dependent winning scenarios against Swampert, but loses to DB Giratina.


Swampert, as mentioned when discussing Poliwrath, is a threat to the core. It hard counters Registeel and goes even with Swampert. However, unless it reaches a Dragon Breath bulkpoint (which cannot be guaranteed and is almost impossible to reach against Raid IV level Giratina), it gets melted by Dragon Breath and loses the matchup hard, even with successful shield baits.


Armoured Mewtwo has a close win with Registeel, is slightly positive against Swampert, and has a close loss with Giratina, which means it can provide value at threatening all members of this core.


Togekiss, Lapras, Articuno, and Cresselia are core breakers to the Giratina + Swampert side of the core, but were not included on the graphic due to having no scenarios against Registeel where they either win or have a close loss. However, if they can avoid Registeel, they present a huge threat to the other two members of the core.



— Cresselia + Charizard + Obstagoon —


A space duck, a not-dragon, and a rock-and-roll weasel walk into a bar...


...and become a trio so strong that two of the challengers are from the core itself! Thriving against the open UL meta, this team has an abundance of coverage for each core partner’s weaknesses.


Cresselia Psycho Cut + Moonblast + Future Sight or Grass Knot^( E)


Much like Azumarill in Great League and Dialga in Master League, there was no escaping Cresselia in UL after the Moonblast buff at the beginning of Season 2. Being able to whittle down most of its counters - and potentially flip the matchup with a fortuitous Moonblast debuff - Cresselia was at its peak of dominance in the second season of GBL. It remains to be seen how much the recent changes to Moonblast affect her popularity, but it is doubtful that Cresselia will be a rare sight in Season 3. Cresselia works very well alongside both Charizard and Obstagoon because she covers a sizable fraction of the meta, including their counters, while they cover the majority of the Steel types that give Cresselia trouble.


Obstagoon Counter + Night Slash + Cross Chop or Gunk Shot or Hyper Beam


Somewhere along the line Linoone learned how to walk upright and punch things, and now it’s terrorizing Ultra League. Oh the wonders of regional-based evolution! Obstagoon has an interesting typing and moveset and has been a welcome addition to UL. It handles Alolan Muk and walls Cresselia’s Ghost threats, while situationally challenging some of the common Steels. Obstagoon goes even with Swampert and covers both Shadow Claw Giratinas for Charizard. Gunk Shot and Hyper Beam are excellent nukes. Cross Chop is useful in the mirror, but against Registeel and others Night Slash is often comparable.


Charizard Fire Spin + Blast Burn^( E) + Dragon Claw


While a bit of a niche pick in Great League, Charizard is anything but that in Ultra. Its ability to take on a similar role to Alolan Marowak in Great League and melt down Registeel—even at a 0-2 shield disadvantage—is the ideal support for Cresselia. Taking down Escavalier, Charmers and the bulky Grass-types that give Obstagoon trouble make it a suitable sidekick for the weasel also, as Charizard nicely rounds out the Moon-Goon duo.




Gyarados Dragon Breath + Aqua Tail^( E) + Crunch


Get out your fresh new Gyarados, it has a good handle on this core! Gyarados is able to toe-to-toe with Cresselia in even-shield scenarios, taking a couple more losses if Cresselia is using Grass Knot. Against Charizard, so long as the Charizard is using Fire Spin and not Wing Attack, it is able to win in any even-shield scenario. It has pretty close wins against Obstagoon in the 0S and 1S, but loses the war of attrition in the 2S.


Shadow Gyarados has a few shifts in wins and losses. It wins against Obstagoon in the 2S and has a cleaner win in the 1S but it loses the 0S. It also loses a lot of its ability to threaten Cresselia, shifting it to need specific shielding scenarios against the different Cresselia movesets. Given that players are much more limited in IV options with Shadow Pokémon, I would recommend checking yours and seeing how it does against this core (and against the meta at large for that matter!)


Swampert Mud Shot + Hydro Cannon^( E) + Earthquake


A real threat to this core is the prevalence of Swampert in UL. That is with good reason as this swampy beast is able to handle much of the meta with its fast, hard-hitting moves and broad coverage. Against this core specifically, it generally loses to Cresselia (yes, even without Grass Knot), strongly wins against Charizard, and can win against Obstagoon in certain even-shield scenarios, namely the 0S and 2S.


Shadow Swampert, similar to Shadow Gyarados, sees a few changes. Its 0S matchups all improve to some degree, not enough to flip the Cresselia matchup in its favor, but it makes it a closer loss. In the 1S, it is able to flip the Obstagoon and non-Grass Knot Cresselia matchups to wins. In the 2S, it now loses to Obstagoon but defeats non-Grass Knot Cresselia. Obviously using Shadow Swampert is resource intensive as it currently requires an Elite charge TM to teach Hydro Cannon.


Melmetal Thunder Shock + Rock Slide + Superpower


Our big lovely Hex Nut Pokémon uses its big metal fists to smash apart quite a few things in UL, this core trio being one of them! The speed of Melmetal’s Rock Slide—a one-hit knockout against Charizard—allows it to win any even-shield scenario except the 2S, which is IV dependent if Charizard uses only Dragon Claw. Against Cresselia, Melmetal wins the 0S against non-Future Sight Cresselia. It wins 2S against all Cresselia and generally the 1S, except against high SP Future Sight Cresselia. Melmetal is able to beat Obstagoon in the 0S scenario on the strength that Superpower brings, but is too frail to withstand Counter and Cross Chop aggregate damage in the 1S and 2S scenarios.


Giratina (Altered) Dragon Breath + Dragon Claw + Shadow Sneak


The Season 1 meta king, Giratina faced three major setbacks the following season: the Ancient Power nerf; the Moonblast buff and rise of Cresselia; and the corresponding increase in Registeel. Giratina beats Charizard in all even-shield scenarios and defeats Obstagoon in both 1S and 2S. Against Cresselia, its only hope is to double shield bait in the 2S scenario. The Shadow Claw variant performs slightly better against Cresselia in the 0S, but struggles against Swampert landing double Earthquake in the 0S or after a bait in the 1S.


Cresselia Psycho Cut + Moonblast + Future Sight


We already lauded Cresselia above, but it is a decent core breaker as well. Technically, the Grass Knot variant is just slightly better for the mirror, but completely forfeits the Charizard matchup against this core. The 1S scenario against Charizard is best described as IV-dependent with both sides able to win. In the 0S, it trends in Charizard’s direction, but the 2S swings in Cresselia’s favor. Against Obstagoon, it wins the 0S and 1S but gets out-spammed in the 2S.


Charizard Fire Spin + Blast Burn + Dragon Claw


Not to belabor the point, but Obstagoon is the weakest against the core mirror, as Charizard goes even with Cresselia (outlined above) and only loses the 2S to Obstagoon.




Shadow Charizard performs pretty similarly as a counter to this trio, not really gaining any advantage over the standard variant against any of these 3. If you choose to go for the Overheat variant on your Shadow Charizard - to avoid needing an Elite TM - then you do win the 0S against standard Charizard but you struggle in the higher shielding scenarios - especially if the opponent shields your Overheat.




Crustle technically beats all 3 of these, losing only to Cresselia in the 0S. Every other even-shielding scenario against Cresselia works out in Crustle’s favor, as well as all even-shield scenarios against Charizard and Obstagoon. The reason we excluded it from the graphic is because it’s perfectly equipped to handle this trio but does not perform well overall in the open UL meta.


Noting that two core members make this list, there are several other options that break the duos contained within this trio core. Empoleon and Honchkrow perform well against Cresselia-Charizard, whereas Alolan Muk and Escavalier threaten Cresselia-Obstagoon.


— Lapras + Swampert + Gyarados —


While stacking three Pokémon that share a type may not seem like a good idea, this triple Water team comes to defy that reasoning. The presented core takes advantage of Grass types being almost non-existent in the Ultra League, and relies on keeping offensive momentum thanks to its wide myriad of positive neutral matchups. Some intricate relationships between the sub-typings of each member of this trio balance out their individual weaknesses.


Lapras Ice Shard^( E) + Ice Beam^( E) + Surf


With incredible bulk and access to a great moveset, Lapras not only hard counters common leads like Articuno and Giratina, it also shines in a lot of neutral scenarios, which tend to go even and usually end in close wins. All of this makes Lapras the ideal opener for this trio. Counter users and certain Steel types like Registeel give Lapras a hard time, and are probably the only situations where it absolutely needs to get out.


Swampert Mud Shot + Hydro Cannon^( E) + Earthquake


Thanks to its quick Earthquake, Swampert can deal with the Steel types that trouble its teammates. It also provides a resistance against Electric type attacks, and even though those are extremely rare, that is a welcome addition for a triple Water team. Swampert provides the heavy hits for this core and severely appreciates when its partners get to burn opposing shields.


Gyarados Dragon Breath + Aqua Tail^( E) + Crunch


The safe switch of choice, Gyarados helps Lapras providing a key resistance to Fighting type attacks, while also completely walling Registeel. Dragon Breath hits fast and hard and allows Gyarados to finish off weakened opponents and carry over an energy advantage into the subsequent matchup. Aqua Tail is prefered over Hydro Pump, providing more consistent performance with shields up as Gyarados now flips a number of close fights in its favour.




Ferrothorn Bullet Seed + Power Whip + Flash Cannon


Ferrothorn dominates against this core. In even shields, it comfortably wins against every member of this trio. Due to its Grass/Steel typing, Ferrothorn resists half of the charge moves coming from this team and only takes neutral damage from the rest, which it still can easily tank thanks to its great bulk.


Other Grass types like Venusaur and Meganium can win against every member of this core, although they have slightly worse matchups against both Lapras and Gyarados.


Cresselia Psycho Cut + Moonblast + Future Sight or Grass Knot^( E)


This core already struggles dealing with Cresselia running her standard moveset, and Grass Knot only makes things worse. As Cresselia’s fastest charge move, Grass Knot bombards Lapras and Swampert with super effective damage, allowing Cresselia to dominate those fights even taking the 2S. Against Grass Knot, Gyarados is the only Pokémon that stands a chance at winning, securing both the 0S and the 2S scenarios, while having an IV-dependent outcome in the 1S. Against Future Sight, Gyarados loses in the 0S, but Lapras wins in the 2S and Swampert can win in the 2S, as long as Cresselia does not shield an Earthquake.


Machamp Counter + Close Combat + Rock Slide


It should not surprise anyone that Lapras loses all even-shield scenarios against Machamp by a wide margin. What may be surprising though is that Gyarados only wins the 2S, as Machamp gets the 0S scenario and 1S without needing to bait. Against Machamp, Swampert needs excellent IVs in order to survive a Close Combat and win the 0S, loses the 1S regardless of its IVs, and wins the 2S at the cost of a shield disadvantage. Shadow Machamp with Cross Chop has very similar results, dropping the 0S against Swampert, but picking up the 2S.


Lapras Ice Shard^( E) + Ice Beam^( E) + Surf


An opposing Lapras is a nuisance for this core. If it matches shield usage, Lapras wins against Gyarados in all scenarios going straight Ice Beam, even if Gyarados baits successfully. Swampert needs to land Earthquake twice in order to win so shielded scenarios tend to go in Lapras' favour.


Obstagoon Counter + Night Slash + Cross Chop or Gunk Shot or Hyper Beam


Obstagoon wins against Lapras in all even-shield scenarios. It gets Swampert in the 1S scenario, but loses the 0S and the 2S, unless Night Slash provides an Attack boost. Obstagoon wins against Gyarados in the 0S and in the 2S, and has a narrow loss in the 1S unless, again, Night Slash does its magic. It is worth mentioning that Obstagoon can flip these losses with a small energy advantage.


Armored Mewtwo Confusion + Psystrike^( E) + Dynamic Punch


Access to Fighting type coverage in the form of Dynamic Punch allows Armored Mewtwo to dominate against Lapras in all even-shield scenarios, no baits required. It loses against Swampert in the 0S, but wins in the 2S, and usually wins in the 1S unless Swampert reaches a deciding Confusion bulkpoint, which requires really good IVs. Armored Mewtwo always loses in the 2S against Gyarados, but one Confusion of advantage can flip this scenario. If Confusion hits a breakpoint and Gyarados does not have near max SP-level Stamina, then Armored Mewtwo can also win in the 0S and in the 1S.




Any number of Grass types could be listed here, but we chose to highlight other options on the graphic save Ferrothorn, this cores hardest counter. This trio is quite flexible due to the relatively low frequency of Grass types in the open UL meta.


Hope you found the graphic and article helpful, and thank you for taking the time to read the full write-up. Please share the post if you found it useful and good luck battling out there!