MissingNo. Challenge is a hack of Pokemon Red. When creating this one-day hack, the author has just learned about modifying the RAM data of Pokemon Red. He was able to change the Pokemon party and he changed the first Gary battle inside the lab of Professor Oak.
The ideas of this hack are very simple: you are forced to go to Professor Oak’s lab and meet Gary. After that, both of you received the very first Pokemon. This Pokemon is not the normal Pokemon you usually know about. In fact, it is strange. And when you battle Gary, his Pokemon are three high-leveled MissingNo with new movesets that never existed. You have to defeat him and play normally after that.
- Mew get weaker when it levels up to lv 100.
- The Pokemon party was changed strangely.