I have an old favorite version of this game, from 99'er Magazine for
the TI, called Robochase. I still play it, and recently modified it.
Changed the robots to Daleks, and added some speech ("Exterminate!",
etc.)
This version has ten robots, and on level 4, introduces "Spunky the
Martian" (or Davros for the Dalek version) who randomly moves around
stomping barriers and robots alike. You get extra points for capturing
him. You have teleportation charges that you can acquire on the screen
that will move you randomly about. You can move only in 4 directions -
they can move diagonally as well.