Chimeras use heavy ferro-fibrous armor for protection, since it is both the only armor plating which provides a protection comparable to ProtoMech armor and cheaper than the standard plating on battlesuits. However, heavy FF armor is extremely bulky, which initially made it useless for the first attempts to build an Inner Sphere copy of the ProtoMech. The solution from IonCore Engineering was simple but extremely rude when compared to the contraptions other companies had: the techs simply removed both the cooling system and the energy grid from the internal framework to make enough room for the additional frames required to hold the armor. But the price for that decision was that Chimeras may not mount 'Mech-scaled energy weapons because of the lack of sufficient power support, and even the support energy weapons carried by battle armor cannot be cooled. This means that Chimeras may only mount ballistic or missile weapons, in other words: it totally depends on ammunition.