Pokémon Supernova Sun and Penumbra Moon is now widely available for VG players! Only a month after Pokémon Ultra Sun & Ultra Moon were released we are presented with the first ROM hack for USUM. Truly explore the Alola region like never before! So let’s get into it but first and foremost, @Dio_Vento, thank you from Project Pokémon!
If you’re familiar with some of his other works from the past such as: Rutile Ruby & Star Sapphire and last year’s hit Nova Sun & Umbra Moon, than you probably know what sort of fun you’re getting yourself into. However, if you’re new to this scene, follow along. Pokémon SnS/PuM is a fully functional ROM hack to use only with Pokémon Ultra Sun & Ultra Moon games. To clarify, you must own or buy the original game(s) to use a ROM hack.
Moving right along, there are four builds available for this ROM hack. Each build holds unique properties so read the descriptions carefully and choose the one most suited for you.
There are four builds available of SnS/PuM! They differ in Wild Pokémon availability. The Expanded Build is the most popular, since it increases the variety of Pokémon found in Alola.
Wild Pokémon are altered so that every non-Legendary (Tapu/UB/Mythical Pokémon count as Legendary) species is available, at the same level as the Leveled Build. Legendary encounters are not changed in this or any Build. Click here to see where you can catch every Pokémon!
This Build is the recommended way to play the ROM hack.
The player will have access to 58% of non-Legendary evolution lines on Melemele Island alone. This access expands to 83% after Akala Island, and 98% after Ula'ula Island. Every non-Legendary evolution line is available before the Elite Four!
By editing anything caught in the Expanded Build to have come from an Egg (and making sure to obey Poké Ball legality), even Pokémon from this Build can be made legal, though not technically legitimate.
All encounter levels are increased to match Supernova Sun & Penumbra Moon's harsh level curve.
This Build also features all of the rarity changes of the Legit Build.
All Wild Pokémon are 100% legit for trade and will not appear as "hacked" by any legitimacy testers.
Most nocturnal Pokémon are available in the day. The converse is true for diurnal Pokémon.
Rare and interesting Pokémon have been moved into more common slots. Fearow, Yungoos, and friends now occupy the rarer encounter chances. The more unique, fun Pokémon like Mimikyu and Stufful are now as common as a Yungoos or Alolan Rattata would have been.
This Build is recommended if you're using the mod to facilitate competitive breeding, Shiny hunting, Pokédex filling, or other such post-game concerns.
Wild Pokémon are the same as in the Legit Build, but are leveled up to keep pace with SnS/PuM's harsh level curve.
It is recommended to use this over the Legit Build for gameplay if you don't want to use the Expanded Build, since the Legit Build's Wild Pokémon will be far behind the level curve.
Anything caught in the Leveled Build just needs a quick adjustment in PKHeX (edit its Met Level) to become 100% trade-ready.
No changes to the Wild Encounter tables of Ultra Sun and Ultra Moon were made.
Pokémon in SnS/PuM:
Bigger variety can be caught in the wild (no version exclusives). Access to all Pokémon evolution lines excluding non-Legendaries before the Elite Four. Also the probability of them holding items is increased significantly. Pokémon that require special evolution items and Pokémon that are capable of Mega-Evolution may be found holding their respective items in the wild. A Pokémon’s special evolution action such as Trade Evolutions and time/location based evolutions has be altered In favor of convenience. And much, much more.
Poké Marts and Items:
The more un-popular items have been purged from Marts and replaced with “competitive” items. Also watch those price tags -the economy is ever changing. In addition to those changes, some items’ effects have been changed. One item was renamed and repurposed, also keep and eye out of a new item: the Restoration Wing! It fully restores your Pokémon’s HP and status conditions. The Restoration Wing cannot be used during battles.
Last but not least, changes to Trainers:
Trainer teams have been re-designed to be more competitive and carry more Pokémon. All island bosses and main foes carry six Pokémon. This is a great training experience for your Pokémon with EXP Share, and for you. Hours of grinding isn’t really necessary as you will level up fairly along your quest to match your opponents. You may find yourself thinking outside of your normal way of play; coming up with new strategies in response to the harsher demand on your team.
Vist Dio_Vento's Pokémon Supernova Sun and Penumbra Moon thread for complete details and to download the ROM hack: