A 5-step guide to getting Pokémon Battle Citadel running on PC — it is a standalone fan game, so there is no ROM to patch.
Use one of the download links on this page. Fan games usually come as a .zip or .rar archive of a few hundred megabytes — there is no base ROM and nothing to patch.
Extract the archive to a normal folder such as Documents. Keep every file together: the game reads its graphics, audio and data from the folder next to Game.exe.
Open the extracted folder and double-click Game.exe. Most Pokémon Essentials games need nothing else installed. Saves go to the game folder or to your Saved Games folder.
Install JoiPlay and its RPG Maker plugin, copy the extracted folder to your phone, then add the game in JoiPlay by pointing it at Game.exe.
There is rarely a native Mac build. Whisky or CrossOver can run the Windows version: create a bottle, then open Game.exe inside it.
Any of these will run Pokémon Battle Citadel. Pick whichever matches your operating system.
Make sure you extracted the whole archive rather than running it from inside the zip, and that the folder isn't in Program Files. Some games also need their latest patch from the creator's thread.
SmartScreen flags most fan games because they are unsigned. Choose More info → Run anyway only for a download you got from the creator or a trusted mirror.
On Android, JoiPlay with its RPG Maker plugin runs most Pokémon Essentials games. There is no reliable way to run them on iPhone.
Usually in the game folder or in Saved Games under your Windows user folder. Copy that file to move your progress to a new version.
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