Well the nomenclature doesn't really help, heh. Tsuguka has no empathy even for other people who have no empathy.
I only settled on "Grenadier" because they are always very heavily armed and we tend to storm places. "Riflemen" is inaccurate because they are not men, and they have way more than basic rifles. "Sapper" or "Pioneer" might actually be closer to the stuff peeps end up doing, but then what about all the times when we just blow up giant blobs of enemies with massive guns?
In the end, they are just kinda multi-role soldiers that sometimes enforce, sometimes infiltrate, but always use massive ordinance...
What do you even call that kind of action? Scouting in force? Artille-recon?