Transmetals

Transmetals are a subgroup of the Beast Wars and Beast Machines characters in the fictional Transformers universe. Ordinary Transformers in the Beast Wars universe have a mechanical robot form and an organic animal form, also known as a "beast mode", which helped them deal with high Energon levels. Transmetals on the other hand are Transformers that due to mutation caused by a powerful energy wave are highly resistant to Energon overload. This mutation also granted them additional abilities and a transport mode. The Transmetal subline of toys was released in 1998 in conjunction with Beast Wars' second and third seasons.