Final gym is in the south west and is a Psychic-type gym in Alfornada. Nemona is there and will wish you the best. The Gym Test is to work up a sweat by doing an Emotional Spectrum Practice. Dendra, a teacher from the school is there to do the training. Copy the movement and you win
After that you face Tulip who has Farigiraf, Gardevoir, Espathra and Psychic Florges.
Beat the gym and Nemona appears with Geeta and discusses that you can now challenge the Pokémon League northwest of Mesagoza
In the school yard, Clive will confirm he is Director Clavell you will find Cassiopeia and it's none other than himself and will then challenge you to a battle. He uses the evolved Starter you and Nemona didn't pick
He then admits he wasn't Cassiopeia but challenged you to see if you were strong enough to face them
Go to the School Yard and it's Penny. She gets Clive to record the battle so it can be sent to Team Star and challenges you. She uses Umbreon, Jolteon, Vaporeon, Leafeon, Flareon and Fairy Tera Type Sylveon
Defeat her and Team Star will disband. It will flash back to when they started before and how Penny wanted to call it quits. Clavell reveals himself to Penny and brings the rest of Team Star's leaders here to meet Penny. Clavell then revokes his order to ban Team Star and says they can continue to exist or return to the academy and that the leaders have to run the STCs to make up for their misuse of school property.
Go to Clavell's office afterwards and he will thank you but Penny comes in and admits to hacking the League for the LP so Clavell asks for privacy while he deals with it
Penny will then call and ask to meet where you first met. Penny says that the League will let things go if she helps work for them. She then gives you TM169
I'm heading to the league now
When there you get an interview from Rika about the gyms you faced and your past. This then shifts to the Elite Test, battling the Elite Four.
The first is Rika who uses Ground-types: Whiscash, Donphan, Dugtrio, Camerupt and Ground Tera Type Clodsire
The second is Poppy who uses Steel-types: Copperajah, Corviknight, Magnezone, Bronzong and Steel Tera Type Tinkaton
The third is Larry, who has changed type to Flying: Tropius, Staraptor, Altaria, Oricorio (PomPom) and Flying Tera Type Flamigo
The final is Hassel who focuses on Dragon-types: Noivern, Dragalge, Haxorus, Flapple and Dragon Tera Type Baxcalibur
After beating them is your final trial. Rika heals all your Pokémon and you go up to face Geeta. She uses Espathra, Gogoat, Kingambit, Avalugg, Veluza and a Rock Tera Type Glimmora
Defeat her and she will walk you back to the entrance where Nemona appears and congratulates you. Nemona wants to battle you but Geeta suggests you take a rest first. They suggest going to Mesagoza for the battle
Everyone shows up to watch
Defeat her and Nemona celebrates and Victory Road is complete
Going back to Arven now I'm not as underlevelled
Defeat him and he says you'll need two extra people for support and so you suggest Nemona and Penny. He then says you should go to the Zero Gate when you're ready, which can be found south east of Medali
This unlocks a new story, The Way Home, after you have completed all three others
Go to the gate and you will all group up and Sada will bring you down into the crater. Koraidon refuses to go down to the crater but with all four of you it goes down, but when you land Koraidon returns to its ball. You have to go to the lab but first you need to disable the four locks remotely at research stations