Kamen Vers

 was a human-Movellan hybrid and scientist, created in secret by the Movellans as a weapon in the Dalek-Movellan War. He built the planet of Mto, so named after the woman who raised him as his "mother", from the debris of human colonist spacecraft pulled out of orbit via the use of a tractor beam.

He planned to create a race of hybrids like himself using skin samples from the colonists, and to find the First Movellan, who he referred to as "the Founder" and his "father". He was ultimately thwarted by the Tenth Doctor and Anya Kingdom, as well as his own mother, who was revealed to be none other than River Song in disguise. No longer able to contain his emotions, his circuits overloaded, destroying him in the process. (AUDIO: The First Son)

Behind the scenes
The name Kamen Vers is an anagram of Mark Seven, who was later revealed to be the First Movellan.