Pocket Monsters (normally shorted as Pokémon) are 649 known species of creatures that inhabit the Pokémon world, of which 648 have been officially revealed. It is implied that there are more waiting to be discovered, however. Inherent to them are several fantastic powers not demonstrated by most real animals, such as manipulation of electricity and fire. Pokémon are shown to exist instead of animals in their world, although animals are also seldom seen in older media. While most Pokémon resemble animals and may behave like them, there are many that do not resemble animals at all; taking on other forms such as plants, inanimate objects, machines, human-like forms or other more enigmatic and exotic appearances. Pokémon inhabit an extremely diverse range of habitats, ranging from the driest deserts to the lushest jungles, the deepest oceans to the highest mountains and everything else in-between, even space and other dimensions. Pokémon take up various ways of living in those places. However, all can be befriended and made into potential allies.
Many Pokémon are known to evolve from or into other Pokémon, a process that typically makes them larger and stronger, and could be seen as the equivalent to "growing up". Pokémon typically know several techniques that they can use in battle or elsewhere, either to defend themselves or their Trainer, or to perform a task. Most Pokémon are known only to say their name.
It is said in many Sinnoh legends that the universe, Pokémon world included, was created by a single Pokémon, Arceus. In a void of nothingness, a single egg came into being, which then hatches into Arceus, the first Pokémon to be in existence. Arceus creates Dialga, Palkia, and possibly Giratina and gives Dialga and Palkia the abilities to control time and space. Giratina is banished into another dimension for its behavior. Then, during very early formation of the world, possibly sooner, Arceus creates Azelf, Uxie, and Mesprit to create willpower, knowledge, and emotion respectively, attributes that are in all modern humans and Pokémon. They dive to the bottom of present-day Lake Valor, Lake Acuity, and Lake Verity, respectively, dubbing the term "the lake guardians." Around this time, Mew came into being, containing the DNA of every Pokémon to exist in the future.
Groudon and Kyogre's great battle
The next to come in to being are Groudon, Kyogre, and Rayquaza. It has been speculated that Groudon was formed deep inside the Earth, from magma, Kyogre was formed by the pressure in the deep sea trenches, and Rayquaza was formed by the minerals of the ozone layer. Another theory exists that the three already existed before the oceans, lands, and ozone layer did, and rather, proceeded to create these components of the planet themselves. Rayquaza proceeds to fly around in the ozone layer, occasionally coming to rest at Sky Pillar. Groudon and Kyogre proceed to create landmass and fill the sea, respectively. A chance meeting turns the two into rivals, and a conflict for dominance over the Pokémon world begins. This battle continues until Rayquaza quells it, causing Groudon and Kyogre to retreat to special caverns, where they rest. The Red and Blue Orbs are created to prevent the reawakening of Groudon and Kyogre, and are left at Mt. Pyre for safekeeping. At this time, Mew may have been plentiful and lived in large numbers. Landmasses such as Mt. Coronet are created, and Regigigas moves the continents, forming various regions. The Sinnoh region is created around Mt. Coronet. During this violent procedure, Stark Mountain is created and Heatran is formed in lava. Arceus creates the Adamant, Lustrous and Griseous Orbs before falling into a never-ending sleep.
Ancient Unown seen in many different languages and ages
Many years after, the prehistoric era begins and the first prehistoric Pokémon come into being. Scientists have proven that prehistoric Pokémon roamed the land, as Fossils and other archaeological remains have been found to contain the DNA of Pokémon. It is possible that the Mew population may have decreased at this stage, as they slowly gave way to other Pokémon species. Evolution has come, separating humans from Pokémon, to create the first humans.
During the Stone, Ice, and Iron ages, the legendary golems are created, and used as keys to seal away Regigigas in Snowpoint Temple. Regirock, Regice and Registeel are hidden in the Hoenn region.
Brass Tower after the fire, 150 years later.
1500 years before modern times, the earliest known system for writing is developed and used at the Ruins of Alph, Tanoby Ruins, and Solaceon Ruins. Archaeologists are currently unsure whether the nearly identical Unown preceded or succeeded the writing system, but it is assumed they share some sort of connection. At this point the Magikarp population mutated and became weaker.
In recent history, 700 years before modern times, Tin Tower and Brass Tower were constructed. These two nine-tier towers were built opposite each other in Ecruteak City. The towers were built to foster friendship and hope between Pokémon and people. The view from the top of the towers was said to be 'magnificent'. In the west was Brass Tower, which was said to awaken Pokémon and in the east was Tin Tower, where Pokémon were said to rest. At the time, an immense silver-colored Pokémon, was said to make its roost atop the Brass Tower, while its counterpart, the glorious rainbow-colored Ho-Oh was said to rest at Tin Tower. However, around 150 years before the games, a lightning bolt struck the Brass Tower. It was engulfed in flames that raged for 3 days. Lugia and Ho-Oh escaped to the skies unharmed. A sudden downpour put an end to the blaze. In-game lore states that three Pokémon died in the fire, but Ho-Oh was able to revive them as the legendary beasts, Raikou, Entei, and Suicune. At around this time, the first Pokémon League competitions started to take place. In the 1990s, the first Pokémon created by scientific engineering, Porygon, is created.
Dialga, Palkia and Giratina on Spear Pillar.
In contemporary history, some years prior to the date, Mewtwo is cloned from Mew, and later escapes and destroys Cinnabar Island's Pokémon Mansion. Soon after, an erupting volcano on Cinnabar Island causes destruction of many areas on the island. Along with that, the leaders of Teams Aqua and Magma reawaken Groudon and Kyogre and they continue their great battle, only to get stopped again by Rayquaza. Groudon and Kyogre retreat to the region of Fiore to rest after their battle.
In modern history, the Sinnoh region has become unusually colder, due to the strange circumstances occurring across the region. The legendary titans of Sinnoh are also awoken by a villainous team; Team Galactic use a Red Chain forged from the lake guardians to summon Dialga, Palkia and Giratina. Their efforts are halted due to interference from the player. At this time, a rip in time-space has occurred, opening a portal to the Distortion World. Giratina escapes into its dimension along with Cyrus, the Team Galactic leader. The entrance to the Distortion World closes returning the Sinnoh region back to normal. Some years after this, Team Plasma attempts to free Pokémon from human capture but for selfish reasons. Reshiram and Zekrom are awoken due to Team Plasma and the player. The player, siding with one of the two dragons, battles against N to test if N's convictions were correct. After this, the player defeats Ghetsis, and N leaves to a distant land with his dragon, while the player keeps theirs.
Pokémon are living creatures that inhabit the Pokémon world, living alongside, and usually helping, humans. Pokémon have been seen within this world as being both supplements and replacements for animals and plants that exist within the real world. Most people respect Pokémon and treat them kindly, yet there exist people who take advantage of them and exploit their abilities for their own gain. Pokémon have feelings and can also understand the human language to some extent. Recreations of natural ecosystems are done with Pokémon. While some Pokémon have abilities that are normal or only slightly distorted from reality, many more Pokémon have abilities that are completely original and have no counterparts within the real world. Other Pokémon are based on legends that exist in our world such as Ho-Oh being based on a phoenix. Most have distinuguishable crys along with weight and height. A special rare trait known as Shiny Pokémon are oddly colored for the indivual species.
In a Sinnoh myth, it is said that Pokémon and people were originally the same species. Over time, some of these creatures split apart from the rest and became humans. This theory has been explored many times throughout the Pokémon world, but not proven. Mew is said to be the ancestor of all life: it evolved into the other Pokémon. The first human recording was during the Stone Age, millions of years before the modern era. Biological taxonomies of cellular and genetic structure have revealed that Pokémon are all actually a single species of life form and that the individual differences between each creature are actually subspecies. This can also explain why Pokémon can variously interbreed with each other. This explores the myth of evolution in the Pokémon world and makes a reference to evolution of animals and humans in the real world.
In modern times, Pokémon commonly undergo a process called evolution. During the course of a Pokémon's development, under certain circumstances specific to that Pokémon's subspecies, it may become a different Pokémon. This change is not merely physical, however, as Pokémon of a higher evolutionary stage have different and usually more powerful base stats than their predecessors, may have different moves that can be learned, and sometimes change their types, though the primary type is usually preserved. Most Pokémon will undergo this process.
Evolution in Pokémon, for most subspecies, is more akin to metamorphosis than to actual evolution. The Pokémon whose evolution is closest to the real-world definition of evolution is Burmy, who takes on a different appearance depending on the environment.
Nearly every Pokémon undergoes some form of reproduction. Fully developed, or Pokémon that passed their baby form can breed with Pokémon of the same egg group. Pokémon that have no genders can only breed with Ditto; baby Pokémon and legendary Pokémon cannot breed at all, with the exception of Manaphy and Phione. Like the majority of real animals, most Pokémon have genders which can sometimes be determined by markings and gender-differences. Usually, a Trainer's Pokémon will breed in a Pokémon Day Care. It is unknown how a Pokémon reproduces, as no one has seen a Pokémon reproduce. Based on this, it is safe to assume that they only reproduce when left alone. Eggs of Togepi and Elekid All Pokémon able to breed lay eggs. Though, nobody has actually seen a Pokémon lay an egg, they apparently appear by the Pokémon. Pokémon usually lay one egg at a time, sometimes, in unusual occasions, lay various eggs at a time. Pokémon eggs are similar to birds' eggs, as they have a hard outer shell that protects the growing, undeveloped Pokémon inside. An egg's shell usually has a pattern reflecting the appearance of the Pokémon inside making each Pokémon egg unique from one another. Pokémon, like animals, are rather protective of their eggs. They sometimes nest them, but usually keep them close to themselves. The growing Pokémon incubates inside its egg until the time come for the Pokémon to hatch. The time it takes for a Pokémon to hatch varies from each Pokémon species and the type of egg. However, placing an egg into a PC will halt the incubation process. Some Pokémon species have a baby form when they hatch from their eggs. Once in their adult stages, these Pokémon are able to reproduce and continue the cycle of reproduction. Most baby Pokémon can only hatch as a baby Pokémon. However, there are some exceptions. Some Pokémon hatch into a more advanced form most of the time, but can also hatch into a baby form when conditions are right.
Pokémon have been enumerated in several different regions by their local Pokémon professors, taking their primary example from Professor Oak, the developer of the first Pokédex. While Oak's initial development only counted the 151 Pokémon native to the Kanto region, by collaborating with the other professors to develop separate Pokédex listings for each region, the National Pokédex, which counts all Pokémon known, currently catalogs 649 Pokémon.
Pokémon are also classified according to several different types, depending on their strengths, weaknesses, and the moves they learn. Each of these types has certain strengths and weaknesses against others, with a total of 17 types identified so far. Pokémon are known to have either one or two types. Pokémon's types can be changed by moves like Soak and Conversion, and through abilities like Color Change.
Credits go to Bulbapedia.