On your first day after becoming Champion, you’ll be in your bedroom, where your Alolan journey first began. After pondering how far you’ve come since then, leave your room to receive a warm welcome from your Mom–and also Hau, who just so happened to visit. According to your buddy, you’ve got guests waiting outside your house.
Without further ado, exit to the south, back towards the entrance of Route 1. You’ll discover that your guests are the members of the Ultra Recon Squad who are in another predicament, albeit a smaller one this time. Following the chaos at Poni Island, some stray Ultra Beasts have been sighted–and who better to call upon to help than the new Champion?
If you desire, you can let the Ultra Recon Squad take you straight to the designated area or you can head there yourself in your own time. The place you want to be is the path to the east of the central crossroad in Ancient Poni Path on Poni Island. You’ll know it’s the right place when you see Hau and a familiar face–Wicke–along the north.
Go around the walls to reach the pair, being mindful of a Collector peeking through a gap to their east, if you didn’t battle him earlier in the game. As you approach the pair, Hau will inform you that up ahead is Poni Grove, where the Ultra Beasts are. If you tried to enter Poni Grove before this point, you’ll have been stopped, but not anymore.
Meanwhile, the ever-friendly Wicke will give you a Big Malasada to congratulate you on becoming Champion.
In this next area, you’ll immediately bump into the Ultra Recon Squad. They will give you 5 Beast Balls to deal with the wandering Ultra Beasts. If you’ve never used a Beast Ball before, they have an abysmal catch rate when used on Pokémon native to Alola, but have a decent catch rate when used on an Ultra Beast.
On the flip side, all other Poké Balls have a very low chance of catching Ultra Beasts. Basically, if you’re hoping to catch an Ultra Beast, Beast Balls are where it’s at. Additional Beast Balls–useful for Ultra Warp Ride–can be purchased from the Entrance area of Aether Paradise (indoors) for 1,000 Poké Dollars apiece.
Never mind exploring Poni Grove for now; we’ll come back here soon enough. Instead, run around in the nearby tall grass to encounter the Ultra Beast.
This is the Ultra Beast that attacked Hala and Hau towards the end of the main story. If playing Ultra Sun, you’ll face the colorful clown-like creature, Blacephalon. This UB has monstrous Special Attack, further augmented by the two-stage boost from its aura. Pokémon with high Special Defense and that resist Fire are recommended.
For attacks, Blacephalon can use Fire Blast and Shadow Ball for STAB damage. Its trump card is Mind Blown, which deals devastatingly powerful Fire-type damage, at the cost of halving its HP. In addition to being a frightening strong move, it can KO Blacephalon if it has under half HP, ruining your chances of capture.
There are a few ways to ensnare this beast. One, you can attempt to use weak moves that don’t reduce Blacephalon’s HP below half, then wait for it to use Mind Blown to reach critical HP, before throwing your Beast Balls and hoping for the best. Alternatively, Mind Blown will fail if your Pokémon has the Damp Ability.
If playing Ultra Moon, the beast that appears before you will be Stakataka, a defensive behemoth. Likewise, its aura will grant it a two-stage boost to its best stat: Defense. Otherwise, it has good Attack and serviceable Special Defense, but tragic Speed–which is a boon for Trick Room teams. Special Attackers are ideal unless you’re very patient.
For attacks, it can use Rock Blast and Iron Head to deal STAB damage, but those will be the least of your concerns. The biggest hurdle is inflicting damage to this brick wall of an Ultra Beast. It can use Iron Defense to bolster its already stellar Defense, although it can only use it twice before capping its Defense.
As we suggested, you should use Special Attackers as otherwise the battle could take all day. However you can use physical attacks to chip away at Stakataka’s HP near the end. Alternatively, Ground-type physical attacks should inflict decent damage, since Stakataka is doubly weak to Ground.
Having successfully captured the Ultra Beast or defeated it, you’ll proceed to the second stage of the operation. Hau will gather everyone’s attention. Afterwards, run around in the tall grass some more to encounter another of the same Ultra Beast. Again, the same strategies apply. Once the battle is over, no matter the outcome, the operation will end.
Afterwards, the Ultra Recon Squad will depart and you’ll then be escorted back home, whereupon it’ll be the next day.