The Constructicons in "Transformers" (1984) were a faction of robots who transformed into construction vehicles, and who could combine into the giant robot Devastator. However, in this film there are two fleets of Constructions: one fleet of disguised individual robots, and the other fleet combines to become Devastator. This is because the ILM VFXperts, who used a extraterrestrial/multi-segmented design for the robots, were unable to design robots who could become robots AND combine. The Hasbro Company suffered a parallel occurrence with Construction toys, and had to release them in two sets, as described above.
There's your answer, Fishbulb.