Hyetology is a good GBA rom hack but it has some bugs as well things that can irritate you like you get a Pokémon of lvl 10 and the wild Pokémon are of lvl 16-19 and you can't escape from them as well. One more thing that will make you mad is that there are some trees which seems to be like normal trees but you can pass through them that's a bug or coding mistake those trees shouldn't be there. Also there's something wrong with the critical hit ratio. It's seems to be increased. All these are irritating but hyetology have some good features that makes it a slightly good rom hack. Hyetology have completely new events that really doesn't related to any anime or game event. Plus the story line is also interesting I would give Hyetology 6 out of 10 as a rom hack.