After passing through Route 10 and defeating some Team Skull Grunts, you take the bus to the top of Mount Hokulani.
Explore Mount Hokulani
At the top, Professor Kukui talks to you about his plans.
After the cutscene, go southeast of the Pokémon Center and talk to the guy there to get a Moon Ball.
Northeast of the Pokémon Center, you find a Level Ball.
You can go down the mountain road to battle trainers if you wish.
The first trainer that you encounter if you go down the mountain road is Office Worker Jessica. She has a level 30 Clefairy. You get 1200 Pokédollars for winning.
Farther down the mountain, there is a slope to the north. Go down it, then go east through the grass to find TM72 Volt Switch.
Go farther south on the road, and you will find a Fast Ball on the left.
South of that, you can find a hidden Rare Candy on the right.
Farther south, you can battle Hiker Thomas. He has a level 30 Alolan Geodude. You get 960 Pokédollars for winning.
South of the Hiker, there is a ramp to the left. Go down to the grass, then go north to find a Heavy Ball.
After you take the Heavy Ball and try to walk away, you battle Golfer Sky. He has three level 30 Miniors (blue, red, and yellow). You get 1800 Pokédollars for winning.
Go north to the edge of this ledge to find a Poké Finder spot.
On the south end of this ledge, you can battle Collector Todd. He has a level 30 Passimian and a level 30 Oranguru. You get 960 Pokédollars for winning.
South of the Collector, there is a one-way ledge. Go down the ledge, then go south through the grass to find a Max Potion.
That is all to be found on the Mount Hokulani road, so go back up to the Mount Hokulani Pokémon Center.
If you battled all of the trainers here, you can battle the Veteran south of the Pokémon Center. Veteran Akira has a level 33 Alolan Persian and a level 33 Absol. You get 2904 Pokédollars for winning. You get TM95 Snarl after the battle.
From there, go north to the Hokulani Observatory. You will meet Molayne at the door. He will give you a Steelium Z.
Hokulani Observatory
In the observatory, talk to the scientist on the right who is looking at a monitor. If you answer his question, he gives you a Stardust.
On the left, talk to the scientist behind the counter to get a Comet Shard.
Go through the doors in the back.
In this hallway, go through the middle door to find Sophocles. He asks you to go find all of the Charjabug for him.
The Charjabug are not inside the observatory, so go outside. After a cutscene, go into the fenced area across from the Pokémon Center. Check near each pile of dirt. The Charjabug are underground next to the piles of dirt. However, one of them is still missing, but watch the cutscene and you will see it going to the left of the bus. Check behind the left side of the bus to find the final Charjabug.
After a cutscene, go through the colorful door when you're ready.
Sophocles's Trial
Your goal is to press the buttons on the corners of the grid to line up the Charjabug on the marks. Pressing each button rotates the nearby Charjabug counterclockwise.
To line up the Charjabug, press the bottom-right button, then the upper-left button.
Before the Totem Pokémon shows up, a wild level 29 Elekid appears instead. Since you are doing the trial, you are not allowed to try to catch the pokémon, so just KO it.
Next, you have to line up another row of Charjabug. Press the bottom-right button, then press the bottom-left button twice
This time, a wild level 30 Electabuzz appears. KO it to continue the trial.
Afterward, Sophocles needs you to line up more Charjabug. This time, they need to be diagonal from bottom-left to upper-right. So press the bottom-left button, then the upper-right button, then the upper-left button twice.
Now a Totem Togedemaru will appear. The Totem Togedemaru is level 33. It can call ally pokémon into battle, such as Skarmory and Dedenne. The Togedemaru is holding a Sitrus Berry that it can use to heal itself. Togedemaru can use the move Spiky Shield, which protects it from attack and also harms the attacker. It can also use Torment, preventing an attacker from using the same move twice in a row.
After you defeat the Totem Togedemaru and any ally pokémon it called into battle, the trial ends. Sophocles gives you the Electrium Z, then shows you the Battle Agency in Festival Plaza, where you can borrow a pokémon and find other trainers to team up with.
Molayne also gives you an item and asks you to take it to Professor Kukui in Malie Garden.
Malie Garden
At Malie Garden, you find Professor Kukui dealing with some Team Skull Grunts. Kukui challenges them to a Battle Royal. Then the boss of Team Skull, Guzma, arrives. You have to battle him.
Team Skull Boss Guzma has a level 34 Golisopod and a level 34 Masquerain. You get 4080 Pokédollars for winning.
Afterward, Kukui gives you a Z-Crystal for your starter pokémon.
Acerola tells you to go through Route 11 on your way to the next trial.