Gotta catch 'em all! One important part of completing a Pokedex is understanding how breeding works in Pokemon. Not all of the critters found throughout various regions can visit the daycare center and make an egg — different egg groups separate them from doing so.

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It's easy to think of only Rock and Ground types, but the Mineral Egg Group has a wide variety of Pokemon among its ranks. Not all Pokemon are created equal, so whether they are known for their strength in battle or iconic nature, some of these pocket monsters stand out among the rest.

10 Sinistea

Sinistea is an adorable Pokemon that isn't here because of its skill in battle. Some trainers just love the thrill of a shiny hunt, and the Black Tea Pokemon offers one unlike any other. It can come in two forms, phony and authentic. Players trying to catch a square shiny authentic Sinistea in the wild only have a 0.000015% chance of finding one. Any trainers that pull that off will always have something to brag about!

9 Magnezone

2017 was the year of Magnezone in VGC play. Combining its bulk with Leftovers, Protect, and Substitute made it a difficult defensive wall for opposing teams to get through. Today, it can still be quite powerful in singles matches as well. Combining Weakness Policy with its ability Sturdy can give it a massive power boost that allows it to sweep through opposing teams.

8 Onix

It's impossible to forget one of the most iconic Pokemon in the Mineral Egg Group. Onix was a part of many important battles in the anime under Brock's care and could almost be considered the mascot of this Rock-type Gym Leader.

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It still has its use in battle as well, just in a unique niche. Onix is a staple in Little Cup on Smogon due to its access to Stealth Rocks and its naturally high Speed and Defense stats. It's thoroughly outclassed in other formats, but we're happy this snakey rock thing has its place to shine.

7 Shedinja

It's easy to forget that Shedinja is in the Mineral Egg Group as it doesn't look like it would fit on the surface. The two things that make this Pokemon truly special are the fact that it has only one HP and its ability Wonder Guard. If a move isn't super effective (Fire, Flying, Dark, Ghost, and Rock type) it won't deal any damage.

While quirky, Shedinja has been used to great effect in VGC events. It has helped players get top placements from Regionals to World Championships. It's tough to use right, but when it works, Shedinja literally can't be beaten.

6 Aegislash

Aegislash is one of those Pokemon that is too powerful to ever lose relevance in competitive VGC. From 2014 to the present, players have been using it to place high in tournaments. Stance Change is an amazing ability that can allow it to become an offensive powerhouse or defensive tank as needed, which offers incredible flexibility for any trainer that uses it.

5 Porygon 2

It might be hard to believe, but Porygon 2 was one of the most important Pokemon in competitive VGC for over three years. Twenty-one separate players used it on teams that won $103,000 across 128 top eight placements. It was also a part of Christopher Kan's team that won the 2017 International Championships.

With an Eviolite for defense, Porygon 2 was, and still is, one of the best Trick Room users in the game. It likely still has a future in VGC and can even hold its own in Ubers on Smogon.

4 Ferrothorn & Ferroseed

Since Miguel Marti de La Torre used Ferrothorn at the Italian Nationals back in 2013, everyone has seen how strong it can be in VGC. In Pokemon Sword and Shield, it maintained that same strength in VGC while also showing itself as a 1v1 threat.

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Even its evolution Ferroseed has a place in battle. It's one of the most versatile defensive Pokemon in all of Little Cup, capable of taking attacks from powerhouses like Staryu, Foongus, Onix, Porygon, and Abra. Overall this entire evolutionary line was made for battle.

3 Metagross

While Metagross is quite powerful all on its own, Mega Metagross was a terrifying force to be reckoned with. Trainers all had to make sure they had counters for it on their team or else risk suffering massive defeats. It may not be as strong now that Dynamaxing is the new norm, it's still got a lot of fight left inside it.

2 Gigalith

No other pure Rock type Pokémon has placed at regional, international, or even world tournaments like Gigalith. Even with its lack of speed, it doesn't need Trick Room to be strong in battle, which is a unique trait. Gigalith has been a common sight in VGC during the Sword and Shield era and we suspect we'll keep seeing it for quite some time.

1 Duraludon

Duraludon was introduced in the most recent generation and has made a colossal impact. Its Gigantamax form isn't just cool — it's destructively powerful as well. Still, plenty of trainers get the most use out of it in its base form due to its impressive stats and the strong variety available from its moveset. It's also the only Steel and Dragon type in the game, so it creates a unique wall of resistance opposing teams will have a hard time getting through.

NEXT: The 10 Best Pokemon From The Monster Egg Group, Ranked