In recent weeks and months, custom formats in the Pokémon TCG have become increasingly popular. They provide unique learning and playing environment unparalleled by the game's normal Standard and Expanded formats due to unique rules and restrictions. If you wish to become a better deck builder or player, custom format tournaments are the perfect opportunity to do so. In my eight years playing Pokémon competitively, I have picked up a great number of deck-building insights. Popularizing Poké Dolls and Pokégears in Lucario & Melmetal Pokémon online decks this season may be my most widely known deck-building contribution, but the unprecedented sandboxes of custom formats gave me the opportunity to innovate many more ways than discovering singular cards. Custom formats have allowed me to refine my strategies and put them to the test on a consistent basis. Reading this article will give you the ability to approach creating your own tournament-ready decks in custom formats like Journey and the Gym Leader Challenge with insights that will put you ahead of the competition!


Hitmonchan Electabuzz Mewtwo

Custom formats have been around for decades in many different forms. Apart from pre-release events (which are designed to promote new products in a casually fun way rather than foster a healthy competitive environment), the oldest custom format was an experimental format known as Prop 15/3. Designed by Wizard's of the Coast in 2000, Prop 15/3 attempted to address the root causes in the ever-expanding unlimited (Base Set-on) format. Unlimited was an environment dominated by the big-basic Pokémon Hitmonchan, Electabuzz, Scyther, and Mewtwo, supported by a huge variety of powerful Trainer cards. While some evolution Pokémon saw success (such as Blastoise and Alakazam), they were used primarily as support for more big-basics rather than acting as attackers on their own. The extra deck space and high energy requirements taken up by most evolution Pokémon made them no match for those powerful Trainer cards, such as Energy Removal. Prop 15/3 attempted to address these problems by limiting players to only 15 trainer cards per deck and limiting players to only three copies of the same card instead of the normal four (Prop 15/3 gets its name from these limitations). While this format only lasted for one tournament, it paved the way for the yearly-rotating Standard format introduced a year later and sparked creativity in Pokémon TCG players in the decades to come.
One of the oldest and most popular custom formats designed by players themselves– a Cube– is a format designed around a limited pool of cards chosen by the Cube's creator in which players build their decks through a process called 'drafting.' Players pass around a random or curated group of the Cube's cards and choose to take one or multiple cards at a time to use for their decks before passing the group of cards to the next player. Much like a pre-release, Cubes are designed around both a limited pool of cards and a restrictive method of deck building. They provide the perfect opportunity for a group of players to experience a custom competitive environment with only limited cards on hand.
Besides Cubes and the official Standard and Expanded formats, custom formats were fairly scarce due to the obvious crucial limitation of playing in-person: every player needs physical cards. During this past year, the explosion of the online tournament scene (which frees that physical limitation) has allowed custom formats to flourish in ways they never had before. Given only a few packs on your account (which, if you need, you can purchase codes for right here on this site), PTCGO's trading system allows for easy access to any number of obscure cards for almost no cost that would otherwise be difficult or time-consuming to find in-person. These online custom formats can live off of card pools magnitudes larger than Cubes could. They most often rely on ban lists applied to a given number of legal sets rather than specifically curated cards like a Cube. This allows for much more creativity in results as well as deck-building.

Where To Begin

Custom formats in this past year have varied wildly in rules and restrictions. Some tournament organizers choose to impose a strict limit of only a couple of legal sets. Some chose to modify rules in the game just like Prop 15/3 by changing the limit on copies of identical cards or cards with the same name in your deck. Whatever the restrictions maybe, the first step is always to become as familiar with them as possible. You never want to be the person to show up to a tournament with an illegal deck and not be allowed to participate! But don't stress about it. There's almost always a way to contact the tournament organizer and often a discord server linked on the limitless page that you can join. If you have a question, don't hesitate to ask, the custom format community is incredibly welcoming.

After you're familiar with the rules, your deck-building process begins. In order to walk you through, I will be using examples from two of the most popular custom formats as of late: the Journey format and the Gym Leader Challenge format. 

The Journey format, created by the highly accomplished Brazilian player Alex Silva, allows Non-Rulebox Pokémon and Trainers in the Sun & Moon-on card pool and contains an extensive ban list. Among the banned cards are commonly used Trainer cards, such as Professor's Research and Boss's Orders, as well as many powerful Non-Rulebox Pokémon. These bans create a fun and skill-intensive environment with a mind-bogglingly large number of viable archetypes to choose from.

The Gym Leader Challenge format, created by another highly accomplished player, Andrew Mahone, allows all Non-Rulebox Pokémon from the Black & White-on card pool, excluding Pokémon with Ancient Traits. Gym Leader Challenge, "GLC" for short, also imposes two additional game rules: players may only include one type of Pokémon in their deck, and only one copy of a card with the same name (excluding basic energies). GLC is known for crazy decklists. Board states that often feature multiple evolution lines from both sides and unexpected moments in games as each player drops unique attackers on their field each turn. The format forces players out of their comfort zone as normal deck-building tactics, such as relying on a singular strategy, fall apart in a singleton metagame where you can have key cards stuck in your prize cards.
When approaching deck building in any format, looking at the entire pool of legal cards is the best place to begin. Even if the format you are playing in has been previously explored, looking at the card pool first will give you an unbiased perspective and build your deck-building intuition. Although it is a hard skill to develop, accurately predicting the outline of a metagame before seeing any results will give you a huge edge against the competition.
A great way to develop this skill is to utilize the game's history. Choose an old World Championship format that you are unfamiliar with, search for which sets were legal at the event, and try to predict what some of the top Pokémon online decks and cards were in that time purely by looking at the available cards in a Pokémon TCG card database. Then, search for tournament results from that World Championships or for the officially printed World Championships decks to see how accurate you were.
Depending on the size of the format you are building for, looking through the full pool of legal cards can be a daunting task, but here are some tips on how to make this process as quick, efficient, and rewarding as possible:

Step 1: Start with the Trainer Cards

The DNA of almost every custom format is the Trainer engines. Typically, every successful deck in a format is based around a combination of the same small group of Supporter and Item cards that allow those decks to be set up consistently and function throughout the game. Trainer cards can be split up into eight categories: 

  1. Draw cards (Professor's Research, Acro Bike, etc.)
  2. Pokémon search (Quick Ball, Sonia, Brooklet Hill, etc.)
  3. Pokémon/Energy recovery (Ordinary Rod, Klara, etc.)
  4. Switching Cards (Switch, Air Balloon, Escape Rope, etc.)
  5. Gusting Cards (Boss's Orders, Escape Rope, Counter Catcher, etc.)
  6. Healing (Cheryl, Max Potion, etc.)
  7. Support (Metal Saucer, Rare Candy, Big Charm, etc.)
  8. Disruption (Galar Mine, Crushing Hammer, Jessie & James, etc.)
(Some cards, such as Mallow & Lana, will fit into multiple categories– in this case, Healing, and Switching)

A format lacking substantially in one of these categories will create deck-building challenges and produce the potential for exploiting your opponent's lack of access to these cards. For example, if you are building for a format where the only switching options reduce retreat cost directly (like Float Stone and Air Balloon), with no regular Switch cards, you can exploit that fact to trap your opponent's support Pokémon active with a no-retreat attack to get free prize cards and time. In a format where you lack good draw options, you may need to consider playing heavy support Pokémon lines in order to make up for that lack of consistency. Looking through the Trainers first allows you to get an idea of the kinds of Pokémon you may need to look out for later. 

Steven's advice  Copycat

Often, if the custom format is large enough, there will be similar Standard formats in the game's history when it comes to Trainer engines and limitations. The aforementioned Journey format has a very similar Trainer lineup to the 2004 season. Steven's Advice and Copycat were the primary draw supporters in 2004 (like Professor's Research and Marnie today), while in the Journey format, Erika's Hospitality (a spiritual reprint of Steven's Advice) Copycat are the primary draw supporters.

Step 2: Look at the Special Energy Cards

Rainbow energy Scramble energy 

This process is much simpler than looking through Trainers. Here you are primarily looking for cards like Double Colorless Energy, Triple Acceleration Energy, and Counter Energy, which will allow Pokémon that rely on heavy energy costs to be powered up in a more reasonable amount of time. A deck like Mad Party could theoretically be extremely powerful in a format you are building for, but a lack of Double Colorless, Twin, and Triple Acceleration Energies could stop the deck from being as powerful as you would expect. Also, keep a lookout for Rainbow-like energies (Rainbow, Blend, Aurora, Unit, etc.), which could allow you to mix typings more easily.

Step 3: Sort through the Pokémon– Find the Magic Number

Almost every format has a magic number– the power level of the format, the number to hit. Currently, in the Standard Format, and especially in the post-rotation Sword & Shield-on format, that number is 320. Most successful attacking archetypes have a way of reaching this number in two fast, resource-efficient hits or one semi-costly hit. If the format has the best deck, normally, that number is related closely to that deck in some way. If the best deck in the format revolves around a decently high HP Pokémon, that number will often be the HP of that Pokémon. If the best deck in the format revolves around a fast-hitting frail Pokémon, that number will often be the damage that Pokémon deals, or twice that damage. Many times the entirety of the top tier decks will be based around the number in some way. If you're looking for attackers to build around, you'll always want to keep that magic number in mind. Make sure you have a strategy to hit it reliably or to survive it and heal.

Zapdos Gyarados Rapid Strike Urshifu

For example, in the current iteration of the Journey format, Gardevoir [CRE], Gyarados [TEU], single-prize Rapid Strike Urshifu [BST], and Zapdos [TEU] have proven to be some of the best Pokémon online decks. They all have one thing in common: the number 150. Both Gyarados and Rapid Strike Urshifu's HPs are 150, and Gardevoir's is only 10 less at 140. Gardevoir's "Brainwave" attack, when using the minimum three required psychic energies, will deal 150 damage. Rapid Strike Urshifu's "Rapid-Fisted Rush" will deal 150 damage given a full bench of Rapid Strike Pokémon with the exception of one Kubfu waiting to evolve. Gyarados's "Distilled Blast" attack will deal exactly 150 damage if four water energies are revealed. While all three of those Pokémon are evolutions that require time and resources to setup, or in Gyarados's case, a decklist filled with tons of water energies, sacrificing potential consistency and comeback cards, Zapdos only requires single energy to deal 80 damage as long as it made its way into the Active Spot that turn. Conveniently, two hits of Zapdos's "Thunderous Assault" will deal 160 damage, reaching 10 damage over that crucial 150 damage barrier. Zapdos's early game pressure can often bring it into an early prize lead which means its 2HKOs are enough to close out the final prize cards. 

Wailord Metagross

Two other top Pokémon online decks in the format, Wailord [VIV] and Metagross [CES], require much more effort to deal high damage than the previously mentioned decks but can make up for this due to the fact that they are above that 150HP threshold. Urshifu's upper limit is 180, and while Gardevoir has no damage cap, it cannot consistently hit numbers much higher than 150 without burning too many resources, and Wailord and Metagross are even able to survive those more costly hits as well (Metagross with the help of Metal Goggles).

Just like Trainers, Pokémon coincidentally can be sorted into eight different categories. Even more often than with Trainers, these categories will overlap.
  • Early-Game Support (Dunsparce [SS] / [CES], Alolan Vulpix [GRI], Duraludon [RCL], etc.)
  • Stable Draw Support (Zoroark-GX [SLG], Magcargo [DX] / [CES], Oranguru SUM, etc.)
  • Instant Support (Crobat V [DAA], Mewtwo [UNB], Drizzile [SSH], etc.)
  • Energy Accelerators (Blastoise [Base], Malamar [FLI], Moltres [CRE])
  • Evolving Pokémon (Magikarp, etc.)
  • Attackers (Eternatus VMAX [DAA], Zoroark-GX [SLG], Mewtwo-EX [NXD])
  • Walls (Altaria [CHP], Wailord-EX [PRC], Chansey [Base])
  • Recovery (Munchlax [UNM], Starmie [EVO], Mewtwo [UNB])
Pokémon that fit into multiple, such as Zoroark-GX [SLG], are often the most promising cards in a format, especially if they are an attacker. It's no surprise that Gardevoir [CRE] is a powerful attacker in the Journey format. It both fills a stable draw support role and an attacker role and is centered around the magic number of the format. Make note of anything your intuition tells you is strong, given your experience in developed formats, especially if they fit multiple roles.

Existing Results

After you've looked at your format's card pool, it’s time to have a look at existing results, if there are any. You'll want to be scrolling through the legal Pokémon in tandem with looking through lists in order to find the succeeding archetypes and potential counters (this can be direct, such as through type-weakness, but can be more subtle such as finding a Pokémon that trades attacks more efficiently against popular decks). Existing results can often give you easy access to the Magic Number, but many newer custom formats haven't had the development necessary for that number to settle. Don't disregard your initial estimates early.

If your format hasn't seen development, you can take inspiration from previous formats you've played or studied. I personally had played in a tournament in the 2004 format and had firsthand experience seeing the power of Steven's Advice and Copycat. So, when I played in my first Journey tournament, I had an immense advantage against the competition who weren't maximizing their Erika's Hospitality counts and barely even playing Copycat at all. There is almost always a format that shares similar aspects to any given custom format (such as limited supporters, type triangles, powerful stall/control decks) that you can take advantage of if you spot the similarities.

Constructing Your Deck

Starmie Zarude V Magcargo

After taking in all the previous advice and your new knowledge of the cards available to you, it's time to start building your deck! In most formats, it's good to start around a core idea. Going into my first Journey format tournament, I chose to build my deck around Gardevoir [CRE], a preexisting archetype in the format, but with the innovation of Magcargo [CES] and a 2004-inspired Trainer engine. This combination of a safe core choice compounded with new ideas was able to result in a tournament win my first time playing the format. Your core idea can be as simple as giving your own take on a popular card or as complex as designing around fulfilling a game-breaking combo you discovered (for example, a Zarude-V [VIV] healing loop with Starmie [EVO] I used in a tournament with only three sets legal: Evolutions, Guardians Rising, and Vivid Voltage). As long as there aren't any glaring issues to the core strategy you chose (such as it being clearly outclassed or weak to an obvious choice for other deck builders in the format), you really can't make a wrong choice. You may not have discovered the absolute objective best deck possible, but if you've followed the concepts in this article and are learning to accurately predict a metagame from the card pool alone, your choice has a good chance of being a top tier contender.

Blastoise Frosmoth Gothitelle

However, core ideas won't always work, especially in 'singleton' formats such as GLC. That's where backup strategies are necessary. If you're playing a water-type deck in GLC based around Frosmoth [SSH]'s energy acceleration, it's easy to include Blastoise [BCR] as backup energy acceleration in case your Frosmoth is unavailable. But there won't always be an obvious backup. In that situation, try to look for other strategies, often similar, that you could effectively superimpose on top of your existing list, preferably with many shared cards. This can be as simple as playing alternate attackers that utilize similar energy costs or as complex as finding a new way to power up your attackers, such as using Gothitelle [FFI] and Dimension Valley [PHF] as a replacement to Gardevoir [NXD] to fulfill a psychic and colorless attack cost with singular psychic energy.

Now that you've decided what strategies you want to build around, you can start to put things together. If you're unfamiliar with the general division between categories of Pokémon and categories of Trainers in a deck, take a look at a few decks in a format you're familiar with (especially if that format is similar to the custom format you're building for), and group the cards in the list using the same aforementioned eight categories I detailed for Trainers and Pokémon. Generally, you'll want to stick to a similar general layout regardless of the format, so long as you have an abundance of options available to you. This was a huge hurdle for me to get over when building for the Gym Leader Challenge format. My first draft of a fighting-type deck contained over 140 cards because I had no clue how to build a singleton deck. I just threw in every card I thought could be good and could never feasibly end up cutting 80+ cards when I considered them all to be 'good.' The trick that I now use to efficiently and effectively build decks in that format is to build portions of my deck (mostly the Trainers) while ignoring singleton rules– adding four Professor's Research, four Marnie, a couple of Cynthia, four Quick Balls, a couple of Pokémon Communication, etc.– as placeholders. Generally, aiming for around 11 draws/search supporter cards has been best in most formats (currently, the Standard format has Crobat V and Dedenne-GX to rely on as supplemental draw support, so we see only 8 draw supporters, but that's not often the case). Add more supporters if many of them are search-based, such as Skyla, or subtract from that number if you have a lot of Items or Pokémon-based consistency. Then, I will go through and individually replace those cards with others that fill the same purpose as designated by my eight categories.

Spell tag Altar of the moone

After building an outline of necessary cards based on an average deck layout, you can start to hunt for individual cards that support your main strategy. In the case of my Gardevoir / Magcargo deck for the Journey format, Blacephalon [CEC], Spell Tag, and Altar of the Moone were must-includes. Blacephalon acted as an additional attacker that could be set up with fewer resources and, alongside Spell Tag damage from throughout the game, could give me the opportunity for a turn to swing the prize trade in my favor by taking additional KOs alongside the normal back-and-forth prize race single-prize formats are known for. Altar of the Moone was a multi-purpose Trainer card for psychic (and dark) decks. While initially, it seems that it only acts as switching out, the Altar of the Moone acts as a disruption card as well because it can bump an opponent's preferred Stadium.


Testing and deck-building are really part of the same process. So much so that before you've even finalized the first draft of your 60 cards, you should begin aspects of what you probably normally consider 'testing.' Remember back to all the other cards in the format that you were considering building around and take another look at any existing results you looked at earlier. Imagine what those potential decks may look like on a surface level and see if there are any glaring weaknesses in your strategy they could exploit or any potential weaknesses in an opponent's strategy you could exploit. Like I mentioned before in the Trainers section, a format with a good amount of support Pokémon and a lack of Switching cards can be a playground for exploitation. This is a perfect opportunity to take advantage of your greater deck-building preparation. 
However, make sure to learn from my mistakes and don't get too caught up in the mind-game aspect of these exploitations! I decided to play in a format in which I discovered it was extremely easy to trap support Pokémon active for free prize cards and time. Given how obvious the flaw was to me, I naturally assumed many of my opponents would employ these trapping strategies. So, I decided to put no support Pokémon on my list in order to beat them. But when I joined the tournament, I was unpleasantly surprised to see every list running the full assortment of bench-sitting support Pokémon and promptly got run over by speedy lists into an 0-2 drop.

At this point, you should be able to complete the first draft of your list. The next step is to test the deck's consistency. Unfortunately, if you don't have someone else to test the format with you, PTCGO's Standard and Expanded ladders won't cut it. They'll have you losing most games on turn three or earlier and will leave you lacking any relevant information. That's where your new best friends, Otis and the rest of the PTCGO AI gang, come in! If you're looking for good gameplay, the AI will not provide you with it in the slightest. However, they will let you play the game and do little to stop you. That makes them the digital card equivalent of playing hands against yourself. It's the perfect tool for testing your consistency engine. This part of deck building is usually the most intuitive. If you're constantly missing something, you probably need more ways to access it. One trick I use during my testing process, in general, is to put in reverse holos or different artworks for card slots that I could potentially replace. If I'm considering cutting a Switch for something else, I'll use a different artwork for one of my Switch, so when it shows up, I'll use a spreadsheet to keep track of whether I want the Switch or any number of different cards in that situation.


Without hours of testing in the format you built for, you won't know how your deck will perform against the creative inventions of others until the actual tournament. Don't put too many expectations on yourself, and don't be disappointed if you fail your first time going into a completely new setting. I've had my fair share of genius ideas that lead to 0-2 or 0-3 drops, but I've also had a fair few bad ideas that ended up working out in the end. Not knowing how your archetype will perform is unique in a game where, by only the second week of a Standard format, everyone has a concrete idea of every archetype and its position in the metagame. Even if you don't achieve what you were hoping for, you've still learned ten times more about the Pokémon TCG through your planning process than any normal tournament can give you. I hope you've enjoyed your time reading through my ideas as much as I've enjoyed sharing them. Thank you!

About the Writer

Jake Gearhart has been playing the Pokémon TCG competitively since the 2013-14 season. Although he is no stranger to the top tables– his most prestigious accomplishment being the title of Regional Champion– he considers deck-building to be his strongest skill and the most enjoyable aspect of the game. You'll find he often shares critical opinions on Pokémon TCG's game design, deck-building, and playing knowledge he's gained over the past eight years and his nostalgia-free love of retro formats after only becoming acquainted with them in recent years.