Chapter 7: Kahuna Olivia
Want a video instead of a text walkthrough for this part? You can find it embedded below:
Part 7: Kahuna Olivia
Dimensional Research Lab
Use Charizard to fly back to Heahea City. Heal up your Pokemon and head to the right. You'll spot Lillie in front of the Dimensional Research Lab. Enter the building and go to the 3rd floor. In this cutscene you'll meat Professor Kukui's wife, Professor Burnet who will tell you about the Ultra Wormhole and Ultra Beasts. After this cutscene you can check out the bookshelves for some lore and speak to Lillie for some plot, otherwise speak to the Professor so you can leave the building.
When you exit the building you'll catch a glimpse of an Ultra Wormhole and have another cutscene with Hau. Head left and then south to Diglett's Tunnel. After speaking with Olivia, head south and take the right side of the fork to find a trainer and a Dusk Ball. Now head back left and use Tauros to smash through some rocks. Grab the Fire Stone behind them. Then head up the stairs and you'll run into some members of the Aether Foundation. They are the counter organization to Team Skull. Continue south and grab the Ultra Ball. You can go south through a little pathway and wrap around to fight another trainer if you want, otherwise continue right.
You'll find a trainer patrolling around a rock and a Zygarde Cell right above this area. Go south from here, you'll run into Team Skull. You'll do a double battle against a couple of grunts with Hau. They should be a piece of cake. Hau will give you a Max Ether when the battle is finished. Exit Diglett's Tunnel onto Route 9. You'll have to battle a police officer here before continuing on the route. Before entering the city you can go south to battle a fisherman and pickup an X Accuracy by investigating the rock and a Net Ball in an Item Ball.
Head into the city. After a short cutscene, make your way to the Pokemon Center to heal up. After that, enter the building accross the street. The Probopass here will give you a letter from Olivia telling you to meet her at the Ruins of Life. He'll also give you a Max Potion. Head right out of town towards the Memorial Hill. In the Memorial Hill you can face off against a number of trainers and find a Cleanse Tag, a Super Repel, a Hyper Potion, and a Dusk Bull. Continue right towards Akala Outskirts and you'll be stopped by Team Skull and the Aether Foundation. Make quick work of the grunt's Raticate and continue to the right.
Here you can pickup TM28 - Leech Life and a Zygarde Cell and battle a number of other trainers. Head north in the Akala Outskirts to enter the Ruins of Life. Before you enter the ruins, you'll be stopped by Team Skull Admin Plumeria. She'll immdeditaly engage in a battle with you. She has a Lv. 25 Golbat and a Lv. 26 Salandit. Beat her and continue north. A dialogue will begin with Burnet and Lillie. Olivia will then come and challenge you to a battle. Accept the challenge when you're prepared.
Kahuna Olivia will have a Lv. 26 Nosepass, a Lv. 26 Boldore, and a Lv. 27 Lycanroc. Watch out for the Z-Move Continental Crush from Lycanroc, it will likely one-hit KO any of your Pokemon. A strong Water, Grass, or Fighting type will make this battle much easier. Olivia will also use a Super Potion to heal, so be ready for that. When you beat her, she'll give you the Rockium Z and a cutscene will give you direction on where to go next. Your Grand Trial will be complete.