By injecting animal DNA into uryuom eggs, which were provided solely by Mr. Guyur thanks to his mutation, they were able to make three assassins, one with 50% human and 50% animal DNA (Guineas), one with 75% human and 25% animal DNA (Hedge), and one with DNA from a variety of animals, human DNA, and uryuom DNA (Vlad). However, the project was flawed because the scientists were unable to speed up the development of the assassins; instead, their aging was apparently slowed. Later on, when the scientists heard of the creation of Damien, they secretly created a fourth assassin in order to combat him. This assassin would be created from a strong human donor, an animal to make him appear to be just another assassin, an uryuom, and a lespuko; this creation would have the name Shade Tail. However