The Mysteron likenesses created are impervious to X-Rays - showing up on X-Rays as though they were conventional photographs - and can only be destroyed by massive amounts of electricity. The re-creation process requires the subject to be clinically dead before the copy is created; in one episode, ("Treble Cross"), World Air Force test pilot Major Gravener, who the Mysterons had attacked and copied, was later resuscitated in hospital, allowing Spectrum to set a trap for the Mysterons by sending the real Gravener out in place of his duplicate. Despite their general ruthlessness, certain storylines have shown that the Mysterons are unwilling to cause agony or resort to torture. In one episode Captain Black releases one of the Angels from a radioactive chamber before she could suffer radiation poisoning (albeit after he trapped her there), although this was a ruse to draw away the Spectrum agents who were tracking him with geiger counters. A novelisation also depicts the Mysterons trapping Captains Scarlet and Blue on a satellite that they plan to obliterate using its self-destruct mechanism, rather than leaving it to plunge into the Sun where the Spectrum agents would die a slower, more painful death.