The Karma-pudgalas (material clusters qua Karma) which come into Udaya (rise) on getting favourable conditions such as Gati (realm of mundane existence), duration, the Pariṇāma (1) (to undergo transformation from one state to another one) of Pudgala (physical substance) and the like.
sāmagrīvaśādudayaprāptasya.
(Prajñā 23.13 Vṛ Pa 459)