Similar to Pokemon Black and White 2; Pokémon Ultra Moon takes place in the same area as Pokemon Sun, Alola but with an alternate storyline, new pokemon to collect and a few new features.Here are the list of changes/additions:1. Story puts emphasis on the legendary Pokémon Necrozma. The core story of the Alolan trails stay the same. Alola map layout is the same with exception of a few new buildings, a new mini-island Ultra Megalopolis and worm hole. 3/4 of the game will feel very familiar to you plot wise if you played the original sun/moon2. New enemy Group: Ultra Recon Squad and Team Rainbow Rocket. You can fight against all team rocket leaders in past games such as Giovanni (Pokémon Red and Blue) to Lysandre (Pokémon X and Y).3. 3 new Ultra Beasts: UB Assembly, UB Burst and UB Adhesive4. 8 trails instead of 7, with the 8th trail captain being Mina.5. New legendary Pokémon Necrozma with Dusk Mane, Dawn Wings, and Ultra forms. You get the forms by absorbing legendary Pokémon Solgaleo and/or Lunala.6. New Partner Cap Pikachu. It's just a Pikachu with Ash's (?) hat. New Lycanroc Dusk Form7. New Z-MovesClangorous Soulblaze - Kommo-oSplintered Stormshards - LycanrocSearing Sunraze Smash - Solgaleo and Dusk Mane NecrozomaMenacing Moonraze Maelstrom - Lunala and Dawn Wings NecrozmaLet's Snuggle Forever - MimikyuLight That Burns the Sky - Ultra Necrozma8. Mega Stones are also returning, but you have to find them9. SOS battles. Now toned down, instead of wild pokemon calling unlimited SOS pokmeon it's just 1 this time10. new clothing options will be available for players to purchase11. Battle Agency. Battle random trainers with rental pokemon. The more battles you win the more rare rental pokemon you get and prizes you earn12. Mantne Surf. As you fast travel from island to island, you can play a mini game where you ride Mantne through the ocean waves and preform tricks racking up points for a while score which can get you rewards.13. Ultra Wormhole. Similar to Mantne surf where you play a mini-game (fly through rings) to travel to the Ultra Space where you fight and collect rare/legendary pokemon the further down you go. In this game you can literally get all legendaries from past generations if you own both games (list provided later on)14. Alola Photo Club. Take photos with your pokemon, and add stamps/borders to the photos taken with more stamps/borders unlocked as you submit more photos15. Totem Stickers. Replacement of collecting Zygard Cells in the original games. By collecting them you can trade them for Totem pokemon.16. New Moves:Mind Blown - Fire-type Move. Learned by UB Burst.Photon Geyser - Psychic-type MovePlasma Fists - Electric-type Move. Learned by Zeraor17. Roto-Loto. You can now be friends with Rotom (your pokedex) and unlock gives you items your pokemon can carry to increase stats such as exp gain,better friendship, more prize money from fighting trainers, faster egg hatching, use Z-move twice during battle, etc18. Pokemon differences between Ultra Sun and Moon. No new alolan forms, but the ones in the original is still present. Here are a list of exclusive pokemon in each:-Ultra Sun-Exclusive PokemonAlolan VulpixAlolan NinetalesHoundourHoundoomCranidosRampardosCottoneeWhimsicottTirtougaCarracostaRuffletBraviaryLurantis (Totem-sized)PassimianTurtonator-Ultra Sun-Exclusive LegendariesHo-ohRaikouGroudonLatiosDialgaHeatranReshiramTornadusXerneasBuzzwoleKartanaDusk Mane NecrozmaUB-Burst-Ultra Moon-Exclusive PokemonAlolan SandshrewAlolan SandslashElectrikeManectricShieldonBastiodonPetililLilligantArchenArcheopsVullabyMandibuzzSalazzle (Totem-sized)OranguruDrampa-Ultra Moon-Exclusive LegendariesLugiaEnteiKyogreLatiasPalkiaRegigigasZekromThundurusYveltalLunalaPheromosaCelesteelaDawn Wings NecrozmaUB-Assembly19. New pokemon aside from those already mentioned:StakatakaBlacephalonPoipoleNaganadelZeraoraHope the list of changes help you in your purchasing decision. If you find anything else, please put it in the comments===Now I'll post my original review of Pokemon Sun:Huge changes to the pokemon formula since Pokemon X & Y, no longer as it's strictly battle and collecting focused (although still present) as they added variety of mechanics to switch things up a bit and to bring more variety in gameplay. Changes include:1. No HMsNo longer do you have to carry around a HM slave (s). This has bothered me in the past games as I have to restrict 1 or 2 slots out of my party of 6 to help traverse certain areas of the world. In the place of HMs there are Poké Rides where you can ride pokemon interacting with them on the world map, some you may not be able to access until you've completed mission within the game.2. Is it super effective?No longer do you have to look up guides online (unless it's your first encounter) to tell if a move is super effective or not very effective against the pokemon you're up against. After you battle a pokemon once, the game will tell you what moves is super effective or not in the battle menu once you encounter the same pokemon the second time.3. No Traditional GymsNo longer do you have to battle your way through gym after gym to prove you're the best out of brute force.There are 4 islands in the game, each of which are controlled by 4 Island KahunasTo get to them you have to get pass Trail Captains and Todum PokemonTrail captain will give you quizzes, side quests to complete, and/or fight in traditional battlesTodum Pokemon. Basically typical pokemon you find the wild, but significantly stronger and have grunts that help them battle.4. Rotom PokédexTypical pokedex, but with a face and personality attached to it.5. Alola FormsBasically different forms of pokemon you seen in previous generations. Either it's there physical form that is different and/or the pokemon's typing6. Z-MovesWith a Z-Ring and a Z-Crystal you can use a pokemon's ultimate move once per battle. It's not like Mega Evolutions where it stays constant7. QR Scanner.You can now scan QR codes to get event pokemon8. Battle RoyalA 4 player free-for-all where the battle ends after all of one's pokemon trainer's faints. They tally the win-losses of each trainer and the one with best stats at the end wins9. Hyper Training.Once a pokemon reaches level 100, they can go through hyper training which can improve a Pokemon's IV10. Poké PelagoYour PC Box now has functionality to it. It's like a day care sort of thing, instead of just depositing your pokemon, you can passively train them in the PC or have them search for items11. Festival Plaza.An online mode where you can battle other trainers and trade with them. You get festial coins for each interaction which you can spend on clothes, shop or upgrade your pokemon's stats. There's also missions you can undertake to get more coins.12. Night and Day phase, New PokemonPokemon Sun goes the traditional time route while Moon does the opposite. In Pokemon Moon if you're playing in the daytime, the game will consider it night time in-game. Some events also play out differently like different Totum Pokemon on the same island/trailIn traditional Pokemon fashion you can only get some pokemon in each version so trading is required either with a friend or if you own both versions. Also some pokemon evolve differently in each version now.I'd say some of overall models of new pokemon are better looking than the last batch in previous iterations of the pokemon series.13. Auto RunYour run is as fast as a bike now, and it has unlimited use. You can now move in all directions instead of the traditional 4 and it feels very fluid14. No RodFishing is now dedicated to specific regions in the world. You cannot fish wherever you want anymore.15. Photo TakingYou can now take Photos of pokemon in the wild.16. Team Skull and Aether FoundationTeam Skull is the new antagonist group like Team Rocket, but they have a new style to them as they try act gangster-ish with their animated hand gesters/movements. They have more personality and have a darker tone to their backstory and mission.Aether Foundation is the opposite of Team Skull as their mission is to cure injured and hurt pokemon. The group is also conducting research on the Ultra Beast (Pokemon) which is a good mystery story in and of itself.17. Graphical UpgradeGame looks better than the last, although there are some pixelation around the edges still. Models look more realistic than before, and the battle animations are more visually impressive. There are some framerate issues on 2v2 battles for some reason, but then again I own the launch 3DS. You may not have the issue if you own the New 3DS? It's a turn-based system so it doesn't really matter much in terms of gameplay, but the slow down is noticeable18. Pokemon RefreshSimilar to Pokemon amie but with more grooming options-Returning mechanics:Pokebank return, you can now transfer all your pokemon to Sun and MoonClothing Options: Although more options are available, it still feel very limited.Mega Evolutions return, but none for new pokemon from what i've discoveredOverall, love the changes to the traditional formula as it gives the Pokemon Series a nice refresh and is more streamline to play.