The Research Probe was a type of probe droid created by the Gray Secant, a Gree research starship, for the purpose of testing the combat capabilities of sentient lifeforms at the Gray Secant's research pylons. The droid came in two identical variations—Mk-II and the more powerful Mk-IV. When the pylons were activated, the Gray Secant would dispatch a trio of Research Probes, Research Combatants, or Research Battlers to that pylon.