From the 1988 Seacons, we have Tentakil, underwater demolitions specialist. He turns into a legged, octopus-like kaiju creature. The body was redecoed as Scylla as part of the Japanese Beast Wars II pirate team.
The combined form of the Universe Micromaster Aerialbots is Superion, an amalgamation of six robots plus their pack-in accessories that serve as connectors, head, and extremities of the gestalt warrior. While in Japan, the original source of the design ( Sixwing , 1992) was available in a collected set, this combiner needed to be purchased one bot at a time in the 2007 Universe release.