Haunter doesn’t evolve by just leveling up, so how can you turn it into Gengar?
This guide will show you the only way to evolve a Haunter in Pokémon Legends: Z-A, including an alternative method to acquire a Gengar.
Despite coming all the way from Gen 1, Gengar remains one of the most reliable special sweepers in the game. As a Ghost/Poison type, its most efficient stats are Special Attack and Speed, making it powerful against slower Fighting and Normal types.
Gengar used to be more problematic in battles, especially during Generations 3-6, where it could have the Levitate Ability, which made it immune to Ground-type attacks. With all that in mind, obtaining a Gengar isn’t as simple as capturing and training its previous evolution forms, Gastly and Haunter.
It is important to note, however, that Abilities aren't present in Pokémon Legends: Z-A. Still, this didn’t hold back many players from adding a Gengar to their teams, most likely due to its Mega Evolution form.
Evolving Haunter in Pokémon Legends: Z-A

Just like in other Pokémon mainline games, a Haunter can only evolve if you received it via trade in Legends: Z-A.
If you’re starting with a Gastly, train it to level 25 first, so you can evolve it into a Haunter. Then, open the game’s menu and head over to the Link Play option. Under Link Play, select Link Trade.
You can use Link Trade in two ways. You can trade Pokémon with other players near you or remotely using the Internet.
If you want to trade via the Internet, you’ll need to become a Nintendo Switch Online member first. Once you gain access to the Nintendo Switch Online connection, enter this Link Code so you can trade your Haunter with another player’s Haunter:
0066-0066
Unlike other trade evolution Pokémon, a Haunter doesn’t require a held item or reach a certain level to evolve. Just getting one from trading is enough, and it will become a Gengar once the process is complete.
How to catch a wild Gengar in Legends: Z-A

If you’re not a fan of trading, you can just skip evolving a Haunter and catch a wild Gengar right away. Continue playing through the story until you get a mission entitled “A Request from the Rust Syndicate.”
In this mission, you’ll unlock a previously inaccessible location inside an old building. This building is situated in an alleyway east of Café Soleil. Upon entering, you’ll find yourself in a warehouse where you’ll encounter two Gengar and a Gastly.
Keep in mind that this method doesn’t guarantee you’ll get a Gengar, but it does give you a chance to catch one without the hassle of trading.
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