While it is not known to evolve into or from any Pokémon, it has a second form, which is activated by triggering an event in the Oath Woods, where Cobalion, Virizion, and Terrakion teach it Secret Sword, and it changes its form permanently as long as it knows Secret Sword. Its original form, Ordinary Form, will then become Resolute Form.
Keldeo was leaked on a photo of a page from CoroCoro magazine on February 13, 2012, and it was officially revealed on February 15, 2012. Its Resolute Form was officially revealed June 13, 2012.
Keldeo is pony-like, with a large, feathery red mane, long, dark blue, ridged eyebrow-like features, and a single cream-colored horn that is slightly curved. The back of its head, as well as its neck, has light blue-and-white-spotted coloration with spiky edges at the lower portion. Its body is cream-colored, with blue hooves. Its blue-and-white-spotted, lifted and feathery tail is comparable to an elaborate feather in a cap.
Gender differences
Keldeo is a genderless species.
Special abilities
Keldeo has the ability to cross water by ejecting water from its hooves. It also changes into its Resolute Form when taught Secret Sword in Oath Woods.
Behavior
Keldeo tends to run about the entire world, running on the surface of seas and rivers.
Long ago, a fire started in the Moor of Icirrus because of a war among people. In this fire, Keldeo was separated from its parents, but together, Cobalion, Terrakion, and Virizion took care of Keldeo. They acted as its parents, and they taught it knowledge and moves for survival. Keldeo eventually grew and even surpassed the three Pokémon. One day, Keldeo took off from the forest with no one knowing why.
When the three meet again, they teach Keldeo the move Secret Sword.
Keldeo has the lowest base stat total of all event-exclusive legendary Pokémon, excluding Phione, whose legendary status is disputed.
Its trait of running across water mirrors Suicune, another quadrupedal Water-type legendary Pokémon.
Despite Keldeo not being legitimately available in Pokémon Black and White, the Legendary Pokémon battle theme plays when Keldeo is battled in-game via cheating.
Origin
Keldeo is most likely based on the legend of the kelpie, a supernatural water horse that sometimes appeared as a lost pony. Keldeo is also likely based on the kirin also referred to as the "Chinese unicorn" which are often depicted with a single backwards curving horn and posses the ability to walk on water. Keldeo also draw inspiration by the character of d'Artagnan from the novel The Three Musketeers. Like d'Artagnan, it is the latest and youngest addition to the group. Keldeo's tail also resembles d'Artagnan's trademark feathered cap.
Name origin
Keldeo may be derived from kelda (Old Norse for spring/fountain) or may be a combination of kelpie, (a water horse from Celtic folklore) and rodeo (a sport involving skills with horses, cows, and other livestock).
This Pokémon article is part of Project Pokédex, a Bulbapedia project that aims to write comprehensive articles on each Pokémon species, as well as Pokémon groups and forms.