It used to be that once you beat a Pokémon game, you filled out your Pokédex and beat the Elite Four ad nauseam until all your Pokémon were level 100. Then you were pretty much done. This is not the case in Pokémon Sun and Moon, which boasts a pretty extensive postgame to explore.
Once you've become the first Alolan champion at the end of Sun and Moon's story, there are still a lot of secrets to uncover and Pokémon to catch. So don't let beating the Elite Four go to your head! You've still got a lot of work to do if you want to become a true Pokémon master.
Pokémon Sun and Moon postgame guide: Tips and tricks for filling out your Alolan Pokédex
Back in Gen 1 and 2, if you wanted all the Pokémon in your Pokédex you had two main options. You could own two Gameboys like some kind of Andrew Carnegie-type and trade with yourself, but this meant playing through both Pokémon Red and Blue or Gold and Silver — which was a little unfeasible timeframe-wise. Alternatively, you could coordinate with a friend or sibling to buy different versions, which also had its own risks — I never did get that Electabuzz from my older brother, even though he promised he was going to catch one for me.
Flash forward to Pokémon Sun and Moon and everything has changed. Nintendo's 3DS can connect to the internet, giving you way more options. By utilizing the Festival Plaza, you can trade with friends (for that old-fashioned feel) or strangers (for that new modern technique). To trade with friends, you'll want to find them in the Festival Plaza, select the big trade button at the bottom and then select Link Trade. Make sure you mark your friends as VIPs so you can find them easily in the future! You can also cast your net really wide and utilize the Global Trade System to get elusive or region-specific Pokémon.
Another easy way to get a lot of those missing Pokédex entries is to take advantage of QR Codes. They're pretty easy to utilize thanks to the 3DS's built-in camera and can be a great way to fill out some of those missing entries. You only get 10 a day, though, so use them wisely!
Pokémon Sun and Moon postgame guide: How to catch all the legendary Pokémon, including the Island Guardians
If you've been playing through the game normally, you should already have one legendary Pokémon going into the postgame. At the climax of the main story, Nebby (the Cosmog who spent the bulk of the game not getting in Lillie's bag) will evolve into either the Psychic/Steel type Solgaleo or the Psychic/Ghost type Lunala, depending on whether you bought Pokémon Sun or Moon. So you'll have it in your party going into the postgame already.
You can catch another Cosmog after beating the game by going to the Altar of the Sunne or Moone (depending on what version you're playing) in Vast Poni Canyon and participating in a fairly straightforward little scene where another Cosmog will join your party. It'll evolve into Cosmoem and eventually into Solgaleo or Lunala depending on your game. So either level it up until it becomes Cosmoem and trade it to a friend who's got the version opposite yours, or trade legendaries with them in order to get the Pokémon you're missing.
Remember the Tapu Pokémon, Alola's guardians? It's okay if you don't, they get kind of lost in the weeds by the end of the game, when you're a little busy rescuing the head of the Aether foundation Lusamine (and card-carrying dullard Guzma) from an Ultra Wormhole. But once you've beaten the Elite Four, you can head back to each of the ruins you've seen on your journey and challenge the Tapu Pokémon. You'll head to the Ruins of Conflict on Melemele to challenge Tapu Koko, the Ruins of Life on Akala to catch Tapu Lele, the Ruins of Abundance on Ula'Ula to get Tapu Bulu and the Ruins of Hope on Poni in order to find Tapu Fini. More in-depth guides to the Tapus locations can be found in this video embedded below.
Additionally, once you've caught all the Ultra Beasts (which we'll get into below), you'll get the opportunity to catch Necrozma, the psychic type Prism Pokémon. After completing the Ultra Beast missions, talk to Looker, the private investigator who's investigating the legendary Pokémon, and he'll tell you about a black Pokémon he saw flying over Memelele Island. Head to Ten Carat Hill and, eventually, you'll run into Necrozma. It's level 75 and very difficult to catch, so if you've saved your Master Ball, now would be the time to use it.
Pokémon Sun and Moon postgame guide: How to catch the Ultra Beasts
Once you've secured the title of the first Alola champion, a mysterious man will meet you outside your house and give you the Enigmatic Card item. It should go without saying, but this is the only time you should accept a card from a mysterious man who shows up outside your house.
After taking the item, head to the empty motel on Route 8, where you'll meet the mysterious man, Looker, again along with his boss, Anabel, who will challenge you to a battle. Once you defeat her, she and her partner will send you out to catch the Ultra Beasts. She'll also suggest you talk to Wicke at the Aether Foundation in order to get Beast Balls, a special type of Pokéball that works well on these creatures.
You can find a walkthrough of how to get the Ultra Beasts embedded below, but we've also included their locations as well if you're just stuck on one in particular.
Nihilego: Rock/Poison type, level 55, found at Wela Volcano Park or Diglett's Tunnel randomly
Buzzwole (Sun): Bug/Fighting type, level 65, found on Route 2 in Memelele Meadow
Pheromosa (Moon): Bug/Fighting type, level 65, found in the Verdant Cavern
Xurkitree: Electric type, level 65, found in the Lush Jungle and Memorial Hill
Celesteela (Moon): Steel/Flying type, level 65, found in the Haina Desert and Malie Garden
Kartana (Sun): Grass/Steel type, level 60, found on Route 17 and Maile Garden
Guzzlord: Dragon/Dark type, level 70, found in the basement of Resolution Cave near the Seafolk Village
Pokémon Sun and Moon postgame guide: How to get Type: Null and Zygarde's Complete Forme
After defeating the Alolan Elite Four, head to the second floor of the Aether Foundation to find Gladion, Sun and Moon's moody rival-turned-ally. After speaking to him, he'll give you Type: Null, the helmeted Pokémon he used against you in the game, as well as a metric ton of items called "Memory Discs" you can use to change its evolved form, Silvally, into any type in the game. You can evolve Type: Null into Silvally by leveling it up with high happiness. It'll lose its cool helmet, but it's worth it for the Pokédex entry and high variability of Silvally.
Once you finish the main game, the time will also be right to finish collecting those Zygarde cores and cells you've been gathering throughout your adventure. You can use 10 or 50 cells to construct Zygarde's 10% or 50% Forme (inexplicably with an extra "e"), respectively. However, if you collect all 100 cells and cores (95 cells, five cores), you can create a Zygarde with an ability called "Power Construct," that will allow it to shift between its 10% and 50% forms.
This complete Zygarde will also be able to transform into its Complete Forme when either its 10 or 50% Forme reaches half health in battle. Thankfully, Serebii.net has compiled a list of where to find all five cores and 95 cells, since doing so without a guide would probably be very daunting. Once you've got them all, head to the mysterious caravan on Route 16 and get combining!
Pokémon Sun and Moon postgame guide: Battle Royale Dome and the Battle Tree
Pretty early in the game, Professor Kukui will invite you to the Battle Royale Dome to participate in a battle royale with Gladion, Hau and the Masked Royal — who could really be anyone in Alola when you think about it. After that, though, you won't really have much reason to go there until the postgame. Once you're through the main game, the Battle Royale Dome is a great place to earn Battle Points — or BP — a currency you can use to buy held items such as the Power Bracer or the Heat Rock, or Effort Value-enhancing — commonly known as EVs — vitamins such as Carbos and Protein.
Another place you can go to get Battle Points and extend your stay in the Pokémon universe is the Battle Tree, which opens up after you defeat the Elite Four. It's a good place to hone your skills and spend your BP, but here you can use those hard-earned points to get Mega Stones. These are special items you can use to evolve some Pokémon into even stronger forms. They're pricey at 64 BP a pop.
Of course, you're probably going to get the most out of Pokémon Sun and Moon's postgame if you start battling other humans, whether those are your friends or strangers you're meeting through the Festival Plaza. If you do that, you'll want to improve your EVs and IVs, which can make a world of difference in competitive play.
Other than that, it's not a stretch to assume that Nintendo has a plan to keep the content rolling out for Sun and Moon — if the Magearna QR code and the forthcoming official postgame guide are anything to go by. Until we get more QR codes and the official guide, however, the suggestions we've provided above should be enough to keep you occupied in Alola for a while — or maybe just a few more weeks.
More Pokémon news, updates and more
If you're serious about Pokémon Sun and Moon, you'll want to read up so you can be the best. Check out our guides for picking the right starter, Pokémon Sun and Moon cheats, using a damage calculator, how to catch the new legendary Pokémon, how to get Munchlax and picking between Pokémon Sun and Pokémon Moon.