Beast Wars Megatron is an example of a Barneyformer

If a Transformer can convert into a purple and green T-rex, or if it has purple and green colors, it is counted as a Barneyformer. Barneyformers are mostly Decepticons (Predacons in the Beast Era), but it is rare for an Autobot to be a Barneyrformer. So far only two known Barneyformers are identified. These two Barneyformers are called Beast Wars Megatron and Animated Lugnut.