Gondolan is a circular gate captain in Bydo Station. There are two of them in this level, one of them guards a key to a locked gate, the other guards a gold note block. To defeat him, the MK Colation must use their weapons or the brown robots spawning and hit the weak spot (the blue thing). You can also defeat the segments, but the weak spot destoys it all. They attack with bullets, and even if they are defeated, they could still hurt you.
A similar enemy is the Outslay snake, except they don't circle around.