The Pokémon universe is incredibly vast, with countless stories, bits of lore, and legends to keep you reading for weeks. With several seasons of the anime, a few dozen movies, 25 years of games, and shelves of manga books, there is plenty of room for plot holes and leftover mysteries in the Pokémon franchise.

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Today, let's look at the games specifically. There are now eight generations of Pokémon, each with several games, and the world contained within has had several plot points or other strange mysteries left unsolved. Here are some of the more noteworthy mysteries and loose ends in the Pokémon game universe.

10 Multiple Of The Same Legendary

Legendary Pokémon are exactly as their name describes — legendary. These beings are rumored to be the most powerful and fearsome creatures in the Pokémon world, and are often hailed as deities or great powers that rule over the land and cosmos.

With that said, there is typically only supposed to be one of each. Ho-oh and Lugia are respectively ruling over different portions of Johto, Mewtwo is a single experimental creature created in a lab, and so on. So, why is it possible to catch multiple of the same Legendary Pokémon, often within the same game? And, how can they be shiny? If there's only one Groudon, it should either be shiny or it shouldn't.

9 Pokédex Completion

Completing your Pokédex is the ultimate goal of many Pokémon games. A professor, most notably Professor Oak, will give you an empty Pokédex and task you with filling it with every Pokémon in the land. It's an epic quest of tedious and time-consuming proportions, and you'll be rewarded with either a diploma or a "congratulations!" at the end of it.

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But, that's it. It seems sort of anti-climactic. Shouldn't this be a bigger deal? This is especially true considering the professors seem to need your help with the task, but then once you fill the Pokédex, they don't ask for it back or do anything with it.

8 Did You Kill Raticate?

Known as "fanon" — a combination between "fan" and "canon," there are some widely-held theories about the games that are so ubiquitous that some just accept them as truth. There's a great example of this in the Pokémon games.

On the S.S. Anne, the player will battle their rival (Blue) and his Raticate. After this fight, the player will then see Blue at the Pokémon cemetery inside the tower in Lavender Town, and he won't have the Raticate anymore. Many believe that the player killed the Raticate, and Blue was at Pokémon Tower to pay his respects. It has never been proven or disproven, but no one knows where the Raticate went.

7 Burned Tower Reincarnation

This is another old theory that many people just accept as canon these days. In Ecruteak City in Johto, there stands the ruins of a great tower, referred to in-game as the Burned Tower but formerly called the Brass Tower. It's believed by the residents in-game that Lugia once perched there before fleeing to Whirl Islands to escape a great fire. Ho-Oh, which lived next door, revived three Pokémon that died in the blaze, turning them into Raikou, Entei, and Suicune.

Given their visual similarities and matching types, many people believe these three Pokémon were once a Jolteon, Flareon, and Vaporeon. This is further backed up by the Kimono Girls battling with Eeveelutions against the player.

6 Championship Challenges

Almost every region has a resident Champion — a trainer so strong that they take the helm of the Pokémon League and pose the final challenge to aspiring players. Once a Champion is defeated in an official match, the victor becomes the new reigning Champion.

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In most of the main series games, the player's ultimate quest is to defeat the Champion and take the title for themselves. However, before Sun and Moon, the player doesn't really seem to become Champion. Every time you re-battle the Elite 4, the same Champion is waiting for you at the end. Why is the player not considered the new Champion? Luckily, newer games have fixed this, now having you defend your title instead.

5 How Do Poké Balls Work?

This is an age-old question that many long-time players roll their eyes at, but it still hasn't been sufficiently answered. What is inside a Poké Ball? Are gigantic Pokémon like Snorlax and Guzzlord just crammed in there uncomfortably?

Some in-game and anime references state that a Poké Ball creates a friendly environment that a Pokémon finds comfortable. But, how does this work? Is there a tiny little world inside, Magic School Bus-style, or do they teleport the Pokémon somewhere until it's called on to battle?

4 Who Came First?

There are some very conflicting bits of lore in the Pokémon games. One of the most notorious is the "who came first?" paradox. Known as the god of the Pokémon world, Arceus is said to be the "Original One" and that it created the entire universe. At the same time, Mew is said to be the ancestor of all Pokémon. So, who came first?

Some fans say that Arceus is exempt from the "all Pokémon" that descended from Mew, but the games don't confirm this canonically. Also, Arceus is said to have created Dialga, Palkia, and Giratina as its first act of business, so theoretically, they would predate Mew as well.

3 Weird Moves

There are hundreds of Pokémon and a several hundred moves, with countless combinations between the two. One can often deduce if a Pokémon might be able to learn a move using common sense, either because the type matches, or because the move itself somehow matches a physical attribute of the Pokémon.

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But, some moves make absolutely zero sense and even seem like they should be impossible. Why can Gastly, a poisonous ball with no arms, learn Ice Punch? Wooper doesn't have arms either, and it can learn Mega Punch. Zubat, a bat with no eyes, learns Mean Look. The list just goes on and on.

2 Kangaskhan's Baby

This one is a biological head-scratcher. Kangaskhan is a Pokémon inspired by a kangaroo, with a little marsupial's pouch on its belly. Inside, a smaller, purple-colored mini-Kangaskhan is found. It's unclear if Kangaskhan is just one of them, or if the "Kangaskhan" is both of them.

What made this conundrum even more confusing was the introduction of Pokémon breeding in Generation II. Now, you can hatch an egg with a Kangaskhan inside — and it'll already have the little baby. This raises so many questions that it's difficult to even wonder where to start.

1 Ghost Girl

Ghost Girl
via dorkly.com
Ghost Girl

It's unclear why Game Freak feels the need to haunt all of our dreams with this strange girl. This "ghost girl" basically acts like an Easter Egg, appearing in multiple games and being equally creepy in each. In Lumiose City, she'll glide toward you in a building with the lights flashing and say "No, you're not the one" before disappearing.

You can also find her some other buildings, as well as in Mt. Pyre in Omega Ruby and Alpha Sapphire. There are other clues littered around all the Generation VI games, too. There are a ton of theories and creepypasta stories around online, but no one has yet been able to deduce who the girl is, and Game Freak seems to be in no rush to give any answers.

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