Rapid Evolving Items are usually released in generations, or "gens" for short. When a new Rapid EI arrives in the Cash Shop, the 1st generation is available for purchase, containing the starting poses for that item. After a day or two, the item will "evolve", and the starting poses will be added by the new second stage poses. At the same time, the 1st gen of a Rapid EI is still available for purchase from the Cash shop. When a Rapid EI reaches its final stage, it is removed from the Cash Shop, and a 2nd gen that is fully-evolved will be released.