On July 22nd, 2026, the Computer Entertainment Developers Conference (CEDEC), which is Japan’s largest conference for computer entertainment developers to share video game technology and knowledge, held a panel with GAME FREAK Research and Development Department staff members Kai Munakata (宗像快) and Toshihiro Obata (小幡敏宏). Tne Fundamental Design and Operational Case Study featuring the Evolution of the Pokémon Battle System (ポケモン勝負の進化を支える、バトルシステムの基盤設計と運用事例) panel took place from 13:30 to 14:40 JST in PACIFICO YOKOHAMA NORTH.

The battle system in the Pokémon series has repeatedly expanded with each new installment. However, as battle mechanics have grown more complex in recent years and the number of development lines has increased, challenges have arisen regarding development efficiency, maintainability, and scalability.

To address these challenges, GAME GREAK undertook a review and reconstruction of the battle system’s foundational design, successfully building a battle system capable of supporting the maintenance of increasingly complex Pokémon battles.

In this panel, they will introduce the foundational design of the battle system that was rebuilt as part of this initiative. They will also present their approach to expanding and maintaining the increasingly complex game logic across the series while maintaining quality, along with examples of how this approach has been implemented.

『ポケットモンスター』シリーズのバトルシステムは、シリーズを重ねるとともに拡張が繰り返し行われてきました。しかし、近年のバトル仕様の複雑化や、開発ラインの増加に伴い、開発効率や保守性、拡張性に課題がありました。これらの課題を解決するために、バトルシステムの基盤設計の見直しと再構築に取り組み、複雑化するポケモン勝負の保守を実現可能とするバトルシステムを構築することができました。

本セッションでは、この取り組みで再構築したバトルシステムの基盤設計について紹介します。 また、シリーズを通して複雑化していくゲームロジックにおいて、品質を維持しながら、拡張・保守するための考え方と、その運用事例を紹介します。

Pokémon Battle experts from GAME FREAK explain the overly complex battle system used in Pokémon. To manage the vast number of possiblities, a dedicated team was formed starting with Sun and Moon [CEDEC 2026]

The character-raising RPG Pokémon celebrated its 30th anniversary on February 27th, 2026. The Pokémon series, which began with Red and Green, has expanded to include nine series (commonly referred to as "generations") at this time, with several spin-off titles interspersed along the way. With so many series released, it goes without saying that the number of Pokémon, moves, and items featured in the series is enormous.


As of 2026, there are over 1,000 Pokémon, more than 900 moves, and over 200 items. Add to that, there are over 300 Pokémon Abilities.

Faced with such a vast amount of data and combinations, it’s impossible not to wonder about the mechanics of Pokémon battles. At this time, there are 18 different Pokémon types and they each they each have their respective type advantages and disadvantages. Add to that the distinctive behavior of each move and the unique battle systems introduced in each installment of the series.

Just thinking about all these combinations is enough to make your head spin. With all these elements added, what has become of the battle system in the current Pokémon series? The answer, is that it has become more complex!


What’s even more daunting is that in the Pokémon series, it has become something of an unwritten rule that sequels carry over Pokémon, moves, items, and other elements from the previous two games almost exactly as they were. In other words, the more new titles are released, the more the data snowballs. Also, with each new release, over 200 types of data, including new Pokémon and moves, are added.

Given this massive volume of data, what efforts are the creators making to ensure that Pokémon battles, the iconic gameplay of the Pokémon series, remain engaging and fun?

Why was a "battle-speciality team" needed in the first place? A. Because there was simply too much data.

In this presentation, the Pokémon battle system was introduced. In the development process, the Pokémon battle system refers to "the system that determines what happens during a battle". It serves as the link between "What does the player do? (Input)" and "What happens in response to that input? (Output)".


Now that the basis of the battle system had been explained, the conversation shifted to the question: Why was a dedicated battle system team formed in the first place? To put it simply, the reason was that the sheer volume of data and the increasing complexity of the system had reached their limits.

The catalyst for the formation of this specialized team was Pocket Monsters Sun and Moon, which was released in 2016. As mentioned earlier, the current Pokémon generatoin contains an enormous amount of setting data: over 1,000 Pokémon species, over 900 moves, over 200 items, and over 300 Abilities. Since Pokémon is a digital game, all of this data must naturally be handled through program code.


Furthermore, regarding Abilities, as exemplified by Intimidate on Gyarados and Static on Pikachu, they are designed to activate automatically when certain conditions are met, without requiring any input from the player. Additionally, a "chain reaction" can occur, such as when a Pokémon has the Paralyze status condition caused by Static be cured by the use of the Cheri Berry item.

There are cases involving dynamic parameter adjustments, such as Gekkouga's Hidden Ability Protean, which debuted in the 2013 release of X and Y, and a Pokémon's type changes to the type of the move it's using. Due to the interaction of these elements, the current Pokémon battle system has become extremely complex.


In the original Pocket Monsters Red and Green, the system wasn’t nearly this complex; it was much simpler. However, starting with the follow-up Pocket Monsters Gold and Silver, numerous new elements were added, and the battle system underwent expansion after expansion. The development team adopted an approach of gradually expanding the existing system.


That approach reached its limits with Pocket Monsters Sun and Moon. With the new Battle Royale system added in that game, it became clear that the existing expandable framework would struggle to accommodate diverse rule sets, and that adding new features in the future would become extremely difficult.

The increasing size of the functions and files used in the program code also became a problem in terms of maintainability and scalability.

* Battle Royal: A free-for-all battle mode in which four players are divided into separate teams and engage in 1-on-1-on-1-on-1 Pokémon battles.


In response to this, the 2019 release of Pocket Monsters Sword and Shield featured a complete overhaul of the battle system’s basic foundation.

Completely reworking Pokémon battles, which had become very complex! The key was Structuring the battle system.

Of the four principles defined for the battle restructuring were: Structure, Extensibility, Flexibility, and Maintainability but the presentation focused specifically on Structure and Extensibility. With regard to structure, the concept of a "Section" was employed. A Section is a unit that defines only the flow of the processing, specifically, "What to compute and in what order", without including individual Moves or other special features.


Take the Attack stat as an example, there are no special calculation rules for data adjustment, such as multiplying the power of a certain moves by 1.5, like with a Weather※ condition. It's simply a Section for "calculating attack damage."

※ Weather (天気) is a systems mechanic that affects the effects and damage of Pokémon moves during battle. Some Moves can even change the weather itself. It was introduced in Pokémon Gold and Silver as a mechanism limited to certain moves, and then introduced as an independent system in the subsequent Pokémon Ruby and Sapphire games.


The Sections were organized into a hierarchical structure. For example, they grouped Attack power, defense, and the damage calculation into the Damage Calculation Section (ダメージ計算セクション), and placed the Damage Dealing Section (ダメージ付与セクション), which added HP reduction processing to that. By building the system up in this way using reusable Sections, they ensured the overall Structure remained clear and easy to understand.

If they were to directly incorporate elements such as Moves, abilities, and Items, which continue to increase with each new release, into this Structure, maintainability would deteriorate rapidly. To address this, the team introduced Events and the EventHandler.




Each Section triggers Events at key points in the calculations. EventHandlers for elements such as Weather, Abilities, and Items respond to these events and apply adjustments to the resulting output. This approach separates the implementation of individual systems from the main flow of each Section, making it possible to add new features without having to modify the existing program code.

Furthermore, since features that do not appear in a specific title are naturally excluded if no EventHandler is registered for them, title-specific elements such as Mega Evolution and Terastal can also be separated and implemented using the same mechanism, which appears to contribute to both development efficiency and consistent quality.



EventHandlers are also designed to call any Section as needed. For example, in the case with Static, it responds to a reaction event by calling a Section that applies a Status Condition to Paralyze. Then, the EventHandler for Cheri Berry, which reacts to this, performs the Status Condition cure for Paralyze. This behavior is achieved by recursively interweaving "interrupts" and "chains".

Z-A features real-time battles, and the traditional turn-based battles run on the same system.

Once Structure and Extensibility are established in this way, the remaining two design philosophies, Flexibility and Maintainability, are naturally accomplished as well.


As a real-world example supporting the effectiveness of this design, Pokémon LEGENDS Z-A, which features a real-time battle system has a processing structure that is internally identical to the turn-based battle system familiar to fans of the Pokémon series.


The presentation also discussed how the mechanisms of Events and EventHandlers, contribute to the extensibility of the system. In the Pokémon series, battles essentially involve the player selecting commands to determine their actions each turn and then watching the results unfold, a process that could be considered traditional within the RPG genre.

However, behind the scenes lies a vast amount of data accumulated over 30 years, and complex processing runs within a framework built by a dedicated team. At its core is a design philosophy that ensures the Pokémon series continues to evolve and thrive without a hitch.


This panel offered some truly fascinating insights that are sure to change the way fans view the battle system of the Pokémon series.

Sources: https://cedec.cesa.or.jp/2026/timetable/detail/s698585436538b/ and https://news.denfaminicogamer.jp/kikakuthetower/2607224z