By Eco_politiq

When team building, most good trainers do not simply throw together a team of any six Pokemon. They think about things like typing, offensive coverage, weaknesses and resistances, and the kinds of support members of their team need. One very common strategy many players use is called core building, in which the trainer selects 2-4 Pokemon that work well together and can cover one another’s weaknesses and resistances. Core building is a critical strategy in all of the Pokemon metagames; it is particularly crucial in monotype. Here, we will discuss corebuilding strategies, common cores, and their applications in the monotype metagame. I will provide examples of cores whenever possible- being a steel type fanatic, most of my cores will be demonstrated assuming a steel team build, except when impossible.

Top Three Reasons to Use Cores

  1. Ensure that your team has defensive coverage to switch into and absorb dangerous attacks.
  2. Ensure that your team has offensive coverage to handle and not be walled by common threats.
  3. Reduce the chance that a single Pokemon can sweep or wall your entire team.

Some Key Terms for This Blog

Core- 2 to 4 Pokemon on a team that have good offensive and/or defensive synergy, allowing them to handle a bulk of prominent threats with support from other team members.

Synergy- The ability of any two or more Pokemon to perform distinct, complementary roles and assist each other in accomplishing shared goals on a team.

Diversity– The ability for a team to perform multiple functions as a result of using Pokemon that perform different roles.

Niche- The role a particular Pokemon plays on a team or in the metagame as a whole.

*NOTE: While synergy and diversity are related dynamics of corebuilding, they are NOT the same thing! Having good synergy often relies on diversity; however, a team can be very diverse and lack synergy; likewise, a team (usually if it is monotype) can also be synergistic but lack diversity.

Why Cores?

As I have already said, the three main reasons to use cores are defensive synergy, offensive synergy, and team diversity. Unless you are playing monotype, it is unlikely that you will be using multiple Pokemon of a single type on a team. Most trainers will ordinarily build teams that have complementary offensive/defensive typings anyway because it is common sense. Core building takes this a step further- not only do you want to select Pokemon with complementary types, but you also want to consider the niche that Pokemon fills.

One example of an OU core that makes use of these features well is the prevalent Mega Gallade/Bisharp pairing.


This is a common offensive core that makes use of the typing, coverage, and role synergy of the two Pokemon. Mega Gallade’s sky-high attack stat, good speed, and access to Swords Dance make it an excellent wallbreaker/sweeper, while Bisharp functions effectively as a physically oriented wallbreaker. Gallade can switch into and absorb fighting attacks meant for Bisharp and strike back or force the foe out with a psychic attack; meanwhile, Bisharp effectively absorbs flying and ghost type attacks meant for Gallade and can clear away fairies and other threats that resist Gallade’s coverage. They function well together as a core because of their ability to handle one another’s threats and provide enough damage to challenge Pokemon that one could not easily handle alone.

While cores are an important strategy in standard play, they are essential when playing monotype. The reason for this should be fairly obvious: if you are using a team comprised entirely of one type, then multiple members of your team are likely to share weaknesses. If you run a fairy monoteam and do not use Klefki and/or Azumarill, then every Scizor you come across will mow through your team unopposed. Cores are necessary in monotype because they can provide your team with crucial checks and counters to threats that might otherwise 6-0 your team.

Common Core Configurations

While there are a wide variety of different approaches to core building, there are several standard forms commonly used by players. One of the most common cores seen is the Grass/Fire/Water core.


This is a standard core for many reasons. Gamefreak practically designed grass/fire/water cores themselves when establishing the types for all generational starters. Grass/Fire/Water cores have good offensive and defensive synergy alike: grass types resist water and ground supereffective hits meant for fire and electric attacks aimed at water; fire absorbs the fire, bug, and ice hits aimed at grass and the grass hits aimed at water; and finally, water can absorb fire and ice attacks. Offensive synergy is also generally good with GFW cores: aside from their STAB coverage, Pokemon of these types also frequently have access to a wide variety of coverage moves. Varying levels of support, such as spore and leech seed from grass types and will-o-wisp from fire types, also make these cores function well together.

For this example, I used one of my favorite cores, Ferrothorn/Heatran/Empoleon. Heatran is essential when playing mono steel due to the fact that it absorbs fire hits. Empoleon provides additional neutrality against fire and supereffective Scalds to fight fire types off.

Another commonly seen core configuration is the Dragon/Fairy/Steel core.


This core is not legal in a mono steel format due to Dialga being banned, so for this example I am using the core from my gym/E4 PRL challenge. Steel and fairy types absorb dragon moves; steel has a crucial poison immunity and resistances to steel and ice; dragon is in turn resistant to fire. This core works particularly well due to added aspects of its synergy: Latias also has resistances to grass, electric, and fire attacks that threaten Azumarill and Magnezone and is immune to ground thanks to levitate. Azumarill and Latias both resist fighting type attacks as well, and Azumarill can handle dark type attacks other than pursuit aimed at Latias. Magnezone also has an advantage of being able to trap and remove opposing steel types with the combination of Magnet Pull and HP Fire.

A third commonly seen core is the Fighting/Dark/Psychic core.


The core featured here echoes the aforementioned Mega Gallade-Bisharp core, but here I have adapted it to fit steel monotype. Fighting types clear away dark types that threaten psychic allies; dark types can threaten the ghosts that psychics fear and psychic types that make life difficult for fighting; finally, psychic types serve as a good hold-off to most fairies and can handle fighting types that darks are afraid of. Cobalion/Bisharp/Jirachi form an effective steel FDP core that mitigates the fairy weakness a core of this configuration might ordinarily have. Cobalion also has the added bonus of Justified, meaning it can become all the more threatening if it comes in on a predicted dark type attack meant for Jirachi.

Type-Specific Cores

As mentioned previously, in monotype, one needs to consider that many of the Pokemon on their team will have similar weaknesses. Depending on your type, there are some dual type Pokemon available that make it possible to mitigate some of those weaknesses. For example, when playing grass, Cradily serves as a crucial counter against flying and fire type attacks. Some types have more available than others to mitigate weaknesses, but all types have access to at least one or two counters to common threats.

For example, the steel type is weak to fire, ground, and fighting. A common core that I use in my monoteams is Heatran/Skarmory/Doublade.


Heatran’s ability, Flash Fire, allows it to absorb any and all fire attacks that come its way, making it nigh mandatory on any steel team. An air balloon can also be used to provide temporary immunity to ground type attacks. Skarmory is immune to ground as well and also resists fighting. Rocky helmet punishes physical attackers, especially fighting types, while leftovers makes for longevity. Finally, Doublade (Aegislash’s forgotten younger sibling) provides fighting immunity. Doublade is often overlooked simply because it is not as good or popular as its final form. However, its base 150 defense matches Aegislash’s shield form, and Eviolite turns it into a solid physical tank with decent special defense. Its attack stat and movepool also allow it to do a decent amount of damage when played correctly.

All told, the kind of core you compose depends on the type you are using. Some types- like steel, psychic, and flying- have a wide range of dual typed Pokemon in their pool that allow them to cover crucial weaknesses. Others- like grass, rock, and fairy- have only a few options available to them.

Eco’s Five Steps to Building Effective Monotype Cores (AKA the part you probably just skipped to, or tl;dr)

1. Consider the major defensive weaknesses of your type, and identify Pokemon in your pool that can either neuter or provide an immunity to that type.

2. Identify specific Pokemon that pose a threat to your team. Determine their weaknesses, and find the coverage moves needed to KO them.

3. Find overlaps among the different Pokemon and assign roles. When building a defensive core, pay attention to things like weaknesses, resistances, immunities, and recovery. When building an offensive core, pay attention to things like STAB coverage, movepool, and boosting capabilities. Choose Pokemon who are able to provide something that others need.

4. Keep your core to 2-3 Pokemon. Of course, ideally all of the Pokemon on your team will have good synergy, but your core describes the small pact of Pokemon that help you accomplish a major goal. Maybe it’s walling the opponent or stalling them out–in the GFW core I described for steel, Ferrothorn and Empoleon can hazard stack, while Empoleon uses Roar and Ferrothorn sets up Leech Seeds to stall and phaze out the opponent. Either way, your core should comprise a few Pokemon who accomplish their goals best when they have the support of the others.

5. Finally, design the rest of your team to offer primarily offensive support for your core. Make sure that you have the offensive coverage to defeat threats that your core cannot handle, and also consider adding others to cover your cores shared weaknesses. The Ferrothorn/Heatran/Empoleon core accomplishes a shared goal of stalling and phasing foes, but it is weak to fighting; therefore Skarmory, Scizor, and Doublade are good partners.


Most importantly, remember: the core is just one feature of your team. Take it from Ben and Jerry’s: cores are great, but they have to blend with the overall flavor of their surroundings.

And with that, this blog entry has come to a close. I hope you’ve learned something today! Go forth and make good cores!