The Microcons are tiny insect-like Transformers ideal for covert operations. They can combine into the assassin, Reedman.
Revenge of the Fallen film
At one point, Ravage regurgitates the Microcons down a pipe into a highly guarded base on Diego Garcia to steal the All Spark shard. The Microcons form into Reedman, who attacks the guards and steals the shard.