Shadow C.L. (Ciel) is a Promotional Micron exclusive to participating Japanese TRU stores with the purchase of Prime toys. Shadow C.L. (Ciel) is transparent black with a bright purple Energon Crystal and comes as an unassembled kit with a single insignia sticker.
The Arms Microns were ordinary weapons that were suddenly brought to life and given the ability to transform when they were mutated by the Energon found on Earth. These new mini-cons can combine their power to make new weapons for the larger Transformers.