Platforms like Mirai GBA and PokeUniverso often host "pre-patched" versions that combine the NDS enhancements with a 100% Spanish translation.
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To play these fan-made NDS versions, you will typically need an NDS emulator such as SuperNDS for Android or a flashcart (like an R4) if playing on original hardware. Most ROMs come in .nds format and range in size depending on the amount of new content added. Platforms like Mirai GBA and PokeUniverso often host