Achievements for ROM hacks
Can this hack I've found/I've made be a new set on RetroAchievements ?
RetroAchievements opens the doorway to include fun hack sets for players to enjoy. The issue arising in such a broad category open to world of creativity being "What is allowed, and what is not allowed to become a set at RetroAchievements?"
Game Trainer Patches
Not allowed under any circumstance
Hacks that include "game trainers" or integrated cheat features are (for obvious reasons) banned.
Difficulty and Story Hacks
If a ROM hack has sufficient enough differences from the licensed game insomuch that the game can be considered an entirely different game than a unique set is usually acceptable. Consult an admin for specific approval.
Example: Metroid - Rogue Dawn
Beta Release, prototype, bug-fix, re-balancing, and "testing" Hacks
Bug-fix hacks, balance patches, prototype versions, hacks that include development-level integrated utilities (easily accessible Level select, debug menus, menus that display information or provide testing features not normally accessible via the normal game), cannot be linked to core sets, and are typically not allowed to have their own achievement set.
If a rom hack is in a beta state with potential game-breaking glitches, crashes, or bugs, intact as a result of hacking, it is not allowed.
Not allowed - but optional friendly contributions accepted for the original developer
English is the Primary language of RetroAchievements. Translation Patches are sometimes applied by developers to non-English titles as the main MD5 for an achievement set where no licenced English version exists. In these cases patching instructions will be provided in the forum thread of that title. Providing an up-to-spec translation patch for an existing title is possibly allowed to make a game more accessible to other native language speakers. You must deep-memory inspect your translation contribution against the core set and submit it for approval before handing it over to the developer of the set for posting in their thread along with the game.
Sometimes translation patches may critically differ from the developer MD5 in memory differences that you may find online. Before linking these patches check with the original developer or do deep memory tests to ensure total compatibility. You can link translation patches you find online to core sets as long as the game's core achievements all function correctly and do not make the game more or less difficult.
Cosmetic / Sprite Hacks
Cosmetic / Sprite hacks that do nothing to change the original game other than its graphics are not allowed to become their own set. They may be a little fun experience but they are still the same game.
Remember that: If a rom hack has sufficient enough differences from the licensed game insomuch that the game can be considered an entirely different game than its original existing set, it is usually acceptable. Consult an admin for specific approval. A simple sprite hack is not enough to earn a game its own set.
Bonus Set Patches
Cosmetic hacks that produce a unique MD5 for a Bonus Set are possibly allowed to become linked under due review process. They must still be deep-memory tested against the core set to ensure their memory is all in the right place. These involve artful edits to game title screens that must meet specific guidelines. For Bonus Set cosmetic patches to enable a player to reach the Bonus Set instead of the original game set, please speak with Salsa if you intend to help out in creating them. Salsa heads the Bonus Set IPS patch creation sub-community of development for RetroAchievements.
Consult the community via the forum and Discord for review and approval. You can get a good view-port of what the community likes to see by asking. Asking for approval before linking is an integral Developer practice, and falls within your code of conduct as a developer here at RetroAchievements.