These are the internal names of all npcs on this map so that you may spawn them in sandbox using ent_create console command.
Be advised, there's a reason why these are hidden lol, their AI is wonky in sandbox.
Also this list obviously contains spoilers, so if you haven't played you shouldn't be reading this.

npc_c26_boombot_drg - walking landmine
npc_c26_gasmaskcitizen_drg
npc_c26_gasmaskcitizen_tv_drg
npc_c26_invisibleman_drg
npc_c26_lightbug_drg
npc_c26_maintbot_drg
npc_c26_playerghost_drg -- this guy is mostly handled by the map itself so he does nothing in sandbox
npc_c26_playermdl_drg
npc_c26_skeleton_drg
npc_c26_tense_drg
npc_c26_wolf_drg
npc_c26_gc21cop_drg

UNUSED NPCs:
(Thse guys may not even have a model and may even be unfinished, but i'm gonna include them here still as a curiosity thing)
npc_c26_bugcreature_drg
npc_c26_navgoblin_drg
npc_c26_presence_drg
npc_c26_skin_drg
npc_c26_playermdl_giant_drg

At one point a official npc pack would be cool, but as of writing this, I'm very burnt out on SR stuff (what months of constant dev does to a mf) and on a break. If anyone really wants these you can go ahead and make that pack yourself
^^^^
Also to be clear, yes, I give greenlight to anyone who wants to make these npcs better suited for sandbox. All you need to do really is just add the link to the map in the description or just mention where npcs are from somewhere in the description.