This technique is a combination of the Summoning Technique and an Earth Release technique. The user summons a large amount of rock from a giant canyon to be used for other techniques. The user can channel his chakra into the earth to alter the formation, aiding them in sneak attacks. Alternatively, by offering a donation of blood, they can summon a rock in the design of one of Fuen's drawings.
Uitenpen (有為転変) is a Japanese four-character idiom describing the fleeting shifts and changes of human life. The idiom is often translated simply as "mutability".