Duplication is the ability to multiply an object or person.
Users can instantly and exactly replicate targets. Some may be able to make themselves replicate hundreds of times, others may pick up an object and duplicate that instead. Most users have both of these abilities as their clothes are often copied with their bodies. Some also have the ability to remove their copies as quickly as they were made. Biological properties are exactly the same, however each copy will have different experiences and therefore may gain independent personalities over time. Copies always cooperate, always having the same mind, and goals.
666: Satan from The God of High School
Naruto Uzumaki and to lesser extend many other ninjas from Naruto
Tien and several other Dragon Ball characters
Echo from Ben 10
Suwako Moriya, Yuka Kazami and Flandre Scarlet from Touhou