The alien was a would-be conqueror of Earth.
He has green skin, a long head and six legs, wears a green shirt and cape.
He's rather evil, bossy and does not take failure as an option, he prides himself in his schemes and gets annoyed by his clones bumbling.
Scooby-Doo and Scrappy-Doo (second series)
Unfortunately for the invading alien, this was a poor choice for his forum. His clones hijacked a TV show called That's Impossible where impossible things were shown as real. One star of the show was called Daredevil Dan, introduced by the emcee that he will have a two-ton piano dropped on him while he is standing at attention all this time. The pod clones forced Daredevil Dan off stage, then made their announcement that Earth is now part of the alien's empire. The crew released the piano as was intended for Daredevil Dan, harming the pod clones. Afterwards, he decided to go conquer a different planet bringing the malfunctioning clones with him.