"The Apple" and "Obsession" are particularly hard on Security personnel. What is it, at least 7 or more in total over the two episodes?
Nomad kills two(?) in "The Changeling." Two die by accident in "And The Children Shall Lead." The rest are killed individually here and there. We have no idea if any Security personnel were among the 9 casualties mentioned by Spock in WNMHGB. We also don't know if any Security personnel died from their injuries after the alien with its influence departs in "Day Of The Dove."
And it was pretty absurd to assign ANY guards to Nomad period--and then two more? What were hand phasers going to do against it?
The problem in "The Changeling" (one of several major problems in the script, the blue-y
scene being at the top of the heap), is that the guards should have known better not to fire at Nomad, given what had happened at the beginning of the episode. Were they idiots? They should have simply monitored Nomad's movements and reported. Disintegrating the guards, as an unnecessary reply (doubtlessly Nomad was invulnerable to hand phasers) to an essentially implausible provocation, was just gratuitous TV violence.