Throughout the Pokémon games, evolution is key. The monsters can change into something else through leveling up, having an item used on them — or even trading, another key part of the games.

Trading is a staple of the franchise and gone are the days when you had to be next to your friend to do it, connecting your Gameboys by a cable. Now, it can be done from a distance in many games, and some of them even have surprise trades.

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There are a few Pokémon that have an evolution triggered by trading. Many of them involve held items, but these are the Pokémon that trade through the action alone — no frills necessary! Some are more beloved by Pokémon fans than others.

8 Conkeldurr (From Gurdurr)

Conkeldurr is one of the more recent additions to the Dex, a Fighting-type brought to life in Gen V. It has the unique ability to create concrete in Pokémon lore, though this won't help you much in battle.

Overall although it's a cool enough Pokémon, there are simply better Fighting-types to be had. If you're going to go through the trouble of evolutions and trading to create a powerful team, Conkeldurr simply isn't going to be a go-to.

7 Gigalith (From Boldore)

Gigalith is a solid Rock-type, but it doesn't have the nostalgic appeal of Golem, so it ranks lower than another Rock-type evolved by trading. Known as a popular partner for construction workers, it might be a decent enough Rock-type to round out your team, but other than that, it doesn't have too much appeal.

6 Golem (From Graveller)

Golem is one of the classic Gen I Pokémon, and for that, it has a soft spot in the hearts of players who are lured in by nostalgia — which is most of them! But the truth is, there isn't enough about this creature to make it stand out. It's a decently strong Rock-type who will round out your team if that's what you're looking for, just like Gigalith, but it might satisfy fans of Brock too. Alas, neither of the Rock-types evolved by trading are the cutest Pokémon.

5 Gourgeist (From Pumpkaboo)

Gourgeist is a pretty interesting Ghost-type due to the lore around it. It can take on four different sizes, depending on its current target. It's also the only Pokémon, aside from its pre-evolution, that can learn Trick-or-Treat, so the fact it has an exclusive move is pretty awesome and makes it rank highly among the trading evolutions.

4 Machamp (From Machoke)

Machop might just be one of the cutest Pokémon from Gen I, loved by fans everywhere. Its next evolution is a lot more intimidating, however — ever seen a Machoke run at you in the Wild Area? It can be a little bit frightening.

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But after Machoke comes Machamp, with multiple arms and a true Fighting-type spirit. This might just be one of the scariest Gen I Pokémon, and it's one of the strongest Fighting-types you can add to your team. It doesn't have the advantages that a dual-type might, but that means it doesn't have the weaknesses either. If you want to create a classic team and fulfill your nostalgic dreams, Machamp is a solid addition.

3 Trevenant (From Phantump)

Trevenant, simply put, is a pretty cool Pokémon. It's framed as a guardian of the forest, and is vengeful towards those who might harm the forest in any way, such as cutting down trees — and yet, it's known for being particularly kind to the creatures that live there. It's a nice story for a Pokémon to have and even though it might not be the most visually appealing creature, that makes it endearing enough.

Ghost/Grass is also a pretty unusual combination for a Pokémon, making it a nice opponent to have when it comes to type advantages. Unless you're up against Fire, of course.

2 Gengar (From Haunter)

ash's gengar

Despite Trevenant being awesome due to its lore, nothing beats Gengar. Gengar first made an introduction in the anime when Ash had to beat Sabrina and went in search of a Ghost-type, finding Ghastly, Haunter, and Gengar. Although Haunter was the one who ultimately left with Ash and chose to become his Pokémon, fans loved them all for their mischievous nature and the fact that they were portrayed as the only Pokémon who could bring down the mighty Sabrina.

1 Alazkam (From Kadabra)

Speaking of Sabrina! She had a Kadabra, but Alakazam is even stronger.

Alakazam is a pretty tricky creature to get in the games. Abra is quick to use Teleport and disappear, so you need to be quick when trying to catch it or it'll be gone. Its flee rate is also exceptionally high if it manages to break out of the ball you use. But if you can evolve your Abra into a Kadabra and then trade-evolve into an Alakazam, you'll have one of the strongest Psychic-types on your team.

And who doesn't love the nostalgia of Saffron City?

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