Skeletoid

Biology

 * They are essentially technologically advanced suits that have rebeled.
 * They require a living human in order to function, so they capture humans, which the suit can mentally control, and are preserved by the suit to increase their occupant's life span, although the body looks like its decomposing.

Life Cycle

 * The Skeletoids capture a live human, which they put in an empty skeletoid suit, the suit then takes over the subject's body.
 * In time, due to the prolonging effect of the suit on the converted human, it will look decayed.

Trivia

 * They were only featured in the Dr. Who comic made by Marvel, a well known publisher of other famous comics like Spiderman and The X-Men.
 * There is a similar creature, that the Tenth Doctor encounters, known as the Vashta Nerada, which look like shadows. When an exploration team led an expidition into an abandoned library, several members were eaten by those creatures, leaving only the skeleton, the body suit are then used, and later on, it is discovered they could talk with the use of a Data Chip.