The Musta'li-Tayyibis, some of the Ismailis of the late time, generally adhered to the Fatimi philosophy. However, they did add certain additions and adopted a more mythological narrative approach on such subjects as Adam’s descent to earth, the recognition of numerous prophetic cycles, transmigration of the soul after death and the concept of Heaven and Hell. In this study, the Tayyibis' methods to transmigration are discussed in relation to the development of the nafs (soul). According to this, souls who are not yet pure enough to ascend to the "spiritual world" (al-ʿālam al-rūḥānī) will have a chance to advance spiritually by returning to the physical world in various forms or bodies, or by ascending and descending through the seven planetary spheres of hell. After receiving the penalty they earned and realizing the truth, souls in this spiral of cycles, in which they experience numerous deformations, are given the opportunity to be purified once more by accepting the invitation. However, the Tayyibis claim that reincarnation should not be confused with the advancements the soul makes after traveling through numerous stages. Each soul, having passed through these stages and illuminated by the light of the invitation, finally leaves the body and rises to a higher position in the hierarchy where it unites with other venerable souls in the spiritual world.