How to Make Your Own Pokémon Fan Game: A Beginner's Guide

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Everything below is aimed at people who want to study how these games are put together and build something small for themselves. Only ever work from a copy of a game you legally own, keep your project on your own machine, and never sell it or distribute any assets that were not made by you. Treat the whole thing as a portfolio piece and a way to practice, the same way an artist might sketch a copy of a painting they admire.

If that framing sounds limiting, it is on purpose. The parts of this hobby that are the most educational (design, art, systems balance) are also the parts that are completely yours to keep. That is what this guide focuses on.

Why people make fan projects

The usual reasons are: to learn game development end to end on a small scope, to practice pixel art and map design with a clear reference style, to design a personal challenge run with new rules, or to try out a region or story idea that will never officially exist.

It is a great first project because the systems are well understood, the scope of a single route or single gym is tiny, and you get visible progress fast. You can also stop at any layer you want: some people only ever design a fakedex on paper and never touch code.

Pick an era to study

Different Pokémon generations were built on very different hardware, and the amount of work involved in modifying one scales with that hardware. Pick the smallest era that still excites you.

The Game Boy and Game Boy Color era is tiny and approachable: small sprites, simple maps, a manageable number of systems to understand. It is a great teaching target if you are new to low-level game data.

The Game Boy Advance era is the classic hobbyist sweet spot. The sprites are big enough to look great, the maps are expressive, and there is a huge amount of community documentation about how the games are structured internally.

The DS era is more ambitious: 3D map data, dual screens, and richer scripting. Reserve it for a second or third project.

The 3DS and Switch eras are generally out of scope for hobby learning. The tooling is heavy, the file formats are complex, and there is very little that a beginner can do here that they cannot learn faster on an older era.

The two main approaches

There are two broad ways people build on top of an existing Pokémon-style game. The first is binary editing: you open the game's data files in specialized editors and change tiles, text, and scripts in place. It is fast to get started and you see changes immediately, but you are always working around the original structure.

The second is a disassembly project: community-maintained source-code recreations of some older Pokémon games that build back into the same binary. Working from a disassembly is more like normal software development, with version control, code review, and clean history. It is a bigger initial learning curve but scales much better if your project grows.

There is also a third path that avoids the whole ROM question: build an original monster-catching game from scratch in an engine like Godot, Unity, or LÖVE. You lose the nostalgia hook but you get full ownership of everything you make, which is by far the safest option if you ever want to share the result.

Design your region on paper first

Before you open any editor, sketch your region. A single sheet of paper with towns, routes, and gym locations will save you weeks of rework later. Aim for a shape you can actually finish: three towns, four routes, and two gyms is a complete demo. A whole eight-gym region is a multi-year project.

Give each town an identity in one sentence. 'Fishing village on a cliff', 'university town in a forest', 'mining outpost at the base of a volcano'. If you cannot summarize a town that cleanly, players will not remember it either.

Pace your routes. A good route has one main hook (a new type of encounter, a puzzle, a shortcut) and does not overstay its welcome. If a route needs three screens of empty grass to reach the next thing, cut it in half.

Build a small fakedex

Original creatures are more rewarding to design and much safer to share. Start with the types your region needs (the ones that fit the environment and the gym leaders you have planned) and design outward from there.

For each creature, decide the type, a single silhouette, a rough base stat spread (frail glass cannon, bulky wall, balanced attacker), and one signature move idea. Do not draw finished sprites yet. Nothing is more demoralizing than throwing away a polished sprite because the design did not survive playtesting.

Keep evolution lines short. Two-stage lines are easier to balance than three-stage lines, and a small dex of 40 well-designed creatures beats a dex of 150 half-finished ones every time.

Balance the difficulty curve

Pick a level for the champion first, then work backwards. A common shape for a short fan project is: first gym around level 12, second around level 18, then roughly 6 to 8 levels per gym after that, with the champion 4 or 5 levels above the last gym.

Trainer AI in most classic games is not clever. It picks moves based on simple rules and rarely switches. That means challenge comes from team composition and level pressure, not outsmarting the player. Give each gym leader a clear identity (a signature Pokémon, a shared strategy like status spam or weather) so beating them feels like solving a puzzle.

Watch the item economy. Cheap potions early, expensive full restores late. If players can carpet-bomb every fight with revives from the first town, difficulty does not exist.

Build a real playtest loop

Change one thing, save, test, commit. That is the whole loop. The people who finish projects are the ones who never let broken versions pile up.

Keep a simple changelog even if it is just a text file. 'Buffed Route 3 encounter levels, nerfed Gym 2 ace, fixed warp on Route 4'. Future-you will thank present-you every single time.

Once your demo is playable, get one or two trusted friends to run through it privately. Watch them play if you can. The moments where they get lost or bored are the moments you rewrite.

Where to go next

The most transferable skills here are not Pokémon-specific. If you want to keep growing, read a general level-design book (Anna Anthropy's 'A Game Design Vocabulary' is a great starting point), work through a pixel-art tutorial series, and learn just enough music theory to write a two-minute town theme.

If your fan project starts feeling like a real game, that is your signal to rebuild it in an original engine. Godot is free, well documented, and a great fit for a 2D monster-catching game. Everything you learned about maps, encounters, and balance carries straight over, and now the whole thing is yours.

Keep it personal, keep it fun

The point of a project like this is the practice, not the release. Every hour you spend designing a route, balancing a gym leader, or animating a sprite is real game-development experience that will help you on whatever you build next.

Finish small, learn a lot, and keep the results on your own machine. That is the version of this hobby that pays off.