In the Pokémon world, a great deal of advanced technology is shown to be used by humans. Among this technology is the ability to create artificial Pokémon - Pokémon that have not emerged naturally but have been created, either through experiments or indirect means.
These Pokémon, other than being artificially created, are no different from natural Pokémon. They can breed, evolve, be found in the wild, be captured and be trained just as ordinary Pokémon would. Even these Pokémon have DNA which draws from the genetic code of Mew, the supposed ancestor of all other Pokémon besides these.
Known artificial Pokémon
Grimer (and consequently Muk), according to several Pokédex entries, was created from human pollution in a stream which was exposed to x-rays from the Moon. This would make it the first (by Pokédex number) Pokémon to emerge due to involvement from humans. Because of the nature of its development, Grimer is highly toxic and uses Template:Type2 attacks.
Voltorb (and consequently Electrode), according to several Pokédex entries, first appeared at the company where modern Poké Balls were developed. While it is not known why, Voltorb looks strikingly similar to the red and white device, and this likely indicates some level of human involvement. It has been speculated to be a conscious form of energy, a theory supported by its unstable nature.
Porygon was the first Pokémon created deliberately, as the result of an experiment by the Pokémon Lab in Kanto. Silph Co. possesses a report on the Pokémon, calling it the first "virtual-reality Pokémon". It is made up entirely of computer data and programming, and is able to exist in cyberspace. According to some Pokédex entries, there is copy-protection data embedded in the program to prevent illegal reproduction. Also, Porygon does not breathe. Its Pokédex entry in Pokémon Yellow speculates it may be capable of space travel, however, this and other abilities are limited to what is included in its program.
Porygon possesses two evolutions, both possible through artificial upgrades. Porygon2 evolves from Porygon when it is traded while holding an Up-Grade. According to some Pokédex entries, it is designed to work in and explore space. However, its Pokédex entry in Pokémon Platinum states it is unable to reach and explore other planets. Porygon2, unlike Porygon, is not limited to what is contained in its program - it is capable of learning.
Porygon2 evolves into Porygon-Z when traded holding a Dubious Disc. It is apparently a modification of Porygon2, designed for travel between different dimensions. However, it did not work as planned and exhibits erratic behavior. Its body and head are in awkward positions, and is capable of displaying emotion.
Mewtwo is a powerful legendary Pokémon which is the result of gene splicing experiments using the DNA of Mew. According to logs found in the Pokémon Mansion in Kanto, Mew "gave birth" to Mewtwo after an embryo had been developed. This is inconsistent with Pokémon traditionally being born from eggs. It has a somewhat artificial appearance, most notably the tube protruding from the back of its neck. Like Mew, it harnesses powerful psychic energy.
Castform was created by scientists at the Weather Institute in Hoenn. It was created to help the scientists predict the weather - because of this, it has the ability to change its form and type with the weather condition.
#622 Gobitto and #623 Goruugu
Other Pokémon influenced by humans
Some Pokémon that formed naturally are shown to be altered in some way by human involvement.
Burmy create outer cloaks out of their habitat. This may be composed of natural materials, as seen in its Plant Cloak or Sandy Cloak, or of artificial building insulation as seen in its Trash Cloak. Burmy can change its cloak depending on the area it is used to battle in.
Rotom, as a Template:Type2/Template:Type2 Pokémon, has the ability to possess artificial machinery. These include toasters, washing machines, refrigerators, electric fans and lawnmowers. These allow Rotom to learn moves of different types and change its base stats, while its Ghost typing is lost and substituted with one characteristic of the possessed object.
Genesect, a legendary Pokémon, was a different Pokémon many years ago. However, in Isshu, Team Plasma reconstructed it with a metal body, and also gave it items known as cassettes which change the type of one of its attacks.