This is the biggest risk. If you change a number to a text string, or set _hp to 1,000,000 when the game engine only supports up to 99,999, the game will crash upon loading with an error like "TypeError: Cannot read property 'isDead' of undefined."
// pseudocode const file = await readFile(input); let text = await file.text(); if (isBase64(text)) text = decompressFromBase64(text); const data = JSON.parse(text); // edit data... let out = JSON.stringify(data); if (originalWasCompressed) out = compressToBase64(out); downloadFile(out, 'Game.rmmzsave'); rmmzsave editor
Toggle game switches or change variable values to bypass story blocks or trigger specific events. This often requires loading the game's System.json to see readable variable names. This is the biggest risk