Revealing mistake: As Kai's squadron fly across camera, it cuts to Kai in his cockpit with his shadow on his right. But as the camera pans around to get a side view of him, his shadow moves in the other direction revealing them moving the light with the camera. (00:01:55)
Continuity mistake: As Kai's squadron swoops in to fire their 'stingers' at His Shadow's ship, only 3 of the 6 are shown flying at the control pod. But in the next shot as they fly past it with their stingers hitting, it's 4 of them flying away. (00:03:00)
Other mistake: As Kai's squadron are approaching The Fore Shadow, the ship begins to fire its massive web like plasma waves at the planet, and fires over and over continually. Except in close up shots as Kai's squadron are flying around it. Like it completely stops firing in closes ups, though when cutting away suddenly blasts are close enough to it that they would have been coming out during those close ups. (00:03:05)
Continuity mistake: His Shadow's ship, The Fore Shadow, begins to blast the Brunnen-G planet and the shots hit the surface causing massive instant damage seen and heard from space. Each hit charring the ground. When the camera cuts back to the planet a few shots later as the ship continues to fire, the destroyed areas of the planet from before have all moved around, with the giant char marks being inconsistent in where they landed. (00:02:25 - 00:03:10)
Continuity mistake: Kai and his squadron fire their stingers at His Shadow's ship, and it shows the missile like things heading towards part of it with large cable like structures interconnecting the pieces. When the angle cuts as they hit, the explosions appear in huge size instantly and the positions of these cables change quite a bit. (00:03:05)
Continuity mistake: Kai tells his squadron to have good luck and his mouth is hanging open a little after he says that. Then it cuts to a close up before he says "very very good luck" and suddenly his mouth is fully closed before he speaks. (00:02:50)
Continuity mistake: Kai is flying his dragonfly space craft towards an enemy ship in the beginning with his wingmen as they sing. Kai's shadow is cast on the wall behind him on his left, but when the camera cuts to a close up of him, his shadow is suddenly on the other side. (00:02:05)
Plot hole: As the first prisoner is being pulled towards the organ cutter, you see on the wall the exact shape of the body organs for the brain, lungs, heart, liver, stomach, kidneys and testicles/ovaries that serve as guides and a track for tiny saw blades to come out and cut into the person's body to harvest these organs. The problem is these are in a fixed position, which might work for some people. However people are different sizes, shapes, and heights and most wouldn't match up to these blade guides. So a good majority of the people they cut apart to harvest organs out of wouldn't even give them good ones as the blades would cut into the organs and ruin them. (00:25:20)
Continuity mistake: Kai orders his squadron to bring up their stingers on their bug ships, and in a side angle shows them curling up like a scorpion stinger. It then cuts to a close up of one stinger opening and it suddenly changes shape a little. In the side angle it looking more like a shark head with a visible hump on the bottom side, to being almost a perfect round football like shape in the close up. Also the space gas around the ship changes from green to white between shots. (00:02:35)
Answer: From what I'm seeing, the answer seems simple. The robotic heads allow the control of the body they need. However, no mater how advanced you make a robot's body, it will never quite be as flexible and versatile in it's movements and actions as a flesh and blood human body can be in most cases. And if they do put the effort into creating a robotic body with the capabilities they need, and be durable enough to last... it would cost a lot of money. The Cluster has a large influx of constant prisoners that they use for feeding the Lexx and other needs, so human bodies are easy to come by and in vast quantities. Them simply producing robotic heads with the ability to interface with the human nervous system and placing them on the decapitated bodies of expendable prisoners is a hell of a lot more cost effective and easier to do with the technology they have. It's just a cheaper, more effective option for them to have thousands fo 790 Units in production and use without the cost of manufacturing a fully functional and durable robotic body for them.
Quantom X ★