Regardless of which version you're playing, chat to the Ball Guy by the entrance. They will give you a Heavy Ball, which is a rare ball that's good at catch very heavy Pokémon. Next, speak to the staff member up ahead to sign up for the Gym mission.
Know Your Match Ups: Ghost
Spooky Ghost-type Pokémon are weak to Ghost and Dark. Their moves are super-effective against themselves, but do no damage to Normal-types. Meanwhile, they resist Bug and Poison moves and are immune to Normal moves.
For this Gym, we highly advise Dark-types. Ghosts also work of course, but they're liable to receive heavy damage. Candidates include Thievul, which you can evolve from Nickit, and the Liepard wandering around by the bridge to Motostoke Riverbank in the Wild Area.
The Gym mission this time is kind of fun. You'll sit in a spinning tea cup from one of those fairground rides, except it's free-falling. If you rotate the left control stick right (clockwise), you'll spin towards the right. Meanwhile if you rotate left (anti-clockwise), you'll spin left. Your aim is to manouevere through the maze and reach the bottom.
Start by approaching the cup. In the first segment, let the cup fall down by itself. When it falls into the L shape, rotate clockwise so you spin and fall right. The steps below should automatically push you left, but you can spin left to move faster. You should fall towards a diamond shape along the middle. From here, spin left or right, then right or left to continue falling down.
Next, you'll reach a small buffer area. Halfway along, you'll have to beat a Ghost-type trainer to proceed.
Gym Trainer Clove
Clive's Pokémon are all Ghost and Grass-types, so they're weak to Fire, Flying, Ice, Ghost and Dark. The first Pumpkaboo can use Trick-or-Treat to give your Pokémon the Ghost-type and Shadow Sneak, which usually goes first.
Past the trainer, on the right is a teleport pad to return to the entrance. In case you want to enjoy the tea cup ride again! Actually, it's so you can exit the Gym if you're not prepared. Hopefully, that's not you! Carry on south to start the next tea cup segment.
You'll fall towards some steps that push you left. Do absolutely nothing and let the tea cup fall by itself. You should pass through a gap between the steps and a monstrous hand further left. If you spinned the cup left at the beginning, you might gain enough momentum to reach the monstrous hand. But all it'll do is send you flying up. In which case, you can spin right to proceed.
At the bottom, you'll bump into a monstrous hand, which will send you flying up. Spin right so you hit the next monstrous hand. Then repeat for the third hand. You'll start falling a fair distance. After 3 or 4 seconds, start spinning left, so you enter the gap on the left. Otherwise, don't worry, as you'll hit a hand that will send you flying back up so you can try again.
That was pretty fun wasn't it? Anyway, you'll arrive at another buffer area. Lo and behold, there's another Gym trainer to fight.
Gym Trainer Lynne
Who says climate change isn't real? In the Galar region, Corsola have become extinct and only exist as ghosts. It's a pure Ghost, so banish it with a Dark-type if you can. Pay attention to its Weak Armor ability, which lowers its Defence, but boosts its Speed when hit.
In the final segment, the steps below will try and push you right. As you're about to fall off the steps, spin left. If you miss your chance, don't worry, as there's a monstrous hand on the right that will send you flying up. Next, there's a hand pointing downwards that will shove you straight down. Cheeky sod. Spin left into the nearby hand. Then, as you're flying, spin left again.
You'll fall down a fair distance, towards a hand that will propel you all the way up. Now spin right, while following the steps. If you gain enough momentum, you should clear the gap along the middle. When you reach the far right, the hands here will push you all over the place, but you'll always end up at the exit. That's it for the tea cup hi-jinks! Go forward and challenge the last trainer.
Gym Trainer Roy
Roy, 'ere, has two floating Ghost-types. Haunter is weak to Psychic, Ghost and Dark. Normally it would be weak to Ground, but it has the Levitate ability. Meanwhile, Drifblim is weak to Electric, Rock, Ice, Ghost and Dark.
Unless you want to ride the tea cups again, go up the steps to end the Gym mission. Then run through the entrance tunnel to meet the Ghost-type Gym Leader.
Gym Leader Allister
Allister may be a boy of few words, but his Pokémon can definitely do the talking! Galarian Yamask is your first foe. It's weak to Grass, Water, Ice, Ghost and Dark. After hitting it, you may lose your ability. Also, it can use Disable to stop you using a move.
Next, he may send out Mimikyu. This ghastly costumed Pikachu is weak to Ghost and Steel only; essentially, Steel-types are the only safe counter. Its Disguise ability lets it take one hit, without receiving any damage. But it will lose 1/8 of its HP.
He also has a Cursola, which is an evolved Galarian Corsola. It's still a pure Ghost-type, so you don't need to rack your brain. Be cautious of Curse, which when used by a Ghost-type, halves the user's HP and applies a highly damaging curse on its opponent.
Finally, he's got a Gengar that he's not afraid to Gigantamax. This nightmarish phantom is weak to Ground, Psychic, Ghost and Dark. Unless you're extremely confident, Psychic and Ghost-types should be avoided. That's because Gengar is fast and hits like a truck. But it has poor defences.
Send Allister's ghosts to the afterlife (not literally) and you'll receive the Ghost Badge. Afterwards, you'll be given TM77 Hex and a Ghost Uniform. That's your 4th badge, so you're technically halfway through the Gym Challenge! When you're sure you're not being followed by vengeful spirits, exit the stadium back to Stow-on-Side.