Chapter 3: Kahuna Hala
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Part 3: Kahuna Hala
Now that you've completed the Trial of Ilima, you can catch wild Pokémon in Verdant Cavern. Head south to exit when you're ready. Ilima will open the barricade blocking Route 3 when you get outside. The professor will meet up with you and explain the mechanics of Z-Moves. Continue north onto Route 3 and take any path when you get to the fork. You'll find a Heal Ball and two trainers on the upper route, and a Sharp Beak on the lower route. Head left to enter into Melemele Meadow.
Once in the meadow, you'll find Lillie and be tasked to save Nebby. Go left for a Great Ball. If you head left into the meadow you can find an entrance to Seaward Cave. If you're interested in entering, you can find a number of goodies. First you'll find an Escape Rope right next to the entrance. If you take the right-most path you'll find the Never-Melt Ice, the most valuable item in the cavern. If you continue to explore you can pick up a number of other items including a Super Potion, a Star Piece, a Net Ball (Kala'e Bay), a Heal Ball, and a Stardust.
Exit the cave and hop onto a cliff for a Net Ball. Hop off into the meadow to the north and continue in that direction to find Nebby. Make sure to pick up the Poison Barb to the left before investigating him. You'll then exit the meadow and battle with Hau again. He'll have a Lv. 13 Pikachu and a Lv. 14 starter Pokémon. After defeating him and speaking with the professor and company, continue forward on Route 3.
Head south and right and speak to the man in overalls to get a Soothe Bell. Continue south past another trainer and pick up the Super Potion. You can now go back north and face the Red Card trainer next to the bridge if you've defeated all the trainers along Route 2. Red Card trainers will force a switch out of your Pokemon every turn. He'll give you a Red Card for defeating him.
Continue south, picking up the berries along the way, and you'll arrive back on Route 1. Head back to Hau'Oli and heal up if you need to, then head back to Iki Town. After some dialogue, head north and speak with Hala to challenge him to a Kahuna battle.
Island Kahuna Hala specializes in fighting tpye Pokemon, so a good Flying or Psychic type shoud make quick work of him. He has a Lv. 14 Mankey, a Lv. 14 Makuhita, and a Lv. 15 Crabrawler. As long as you have a few Pokemon in the Lv. 14-16 range, you shouldn't have two much trouble with him. He will give you Fightinium Z and your Grand Trial will be complete. He'll also give you a Ride Pager that will let you ride Tauros whenever you want. The professor will then give you TM54 - False Swipe. Lillie will also ask if she can tag along with you on your adventure, and who could say no?