7178_totsters_extra_npc_addon.

This download looks like an addon. You need to extract the downloaded zip and put the addon folder in your Garry's Mod addons folder. You should end up with a directory structure similar to below:

• steamapps
  • common
    • garrysmod
      • garrysmod
        • addons
          • Totsters_Extra_NPC_Addon <-- Addon folder!
            • e.g.
            • lua
            • maps
            • materials
            • models
            • etc

• Totsters_Extra_NPC_Addon/
  • info.txt
  • materials/
    • VGUI/
      • entities/
        • combine_mine.vmt
        • combine_mine.vtf
        • npc_clawscanner.vmt
        • npc_clawscanner.vtf
        • npc_combinedropship.vmt
        • npc_combinedropship.vtf
        • npc_combinegunship.vmt
        • npc_combinegunship.vtf
        • npc_combine_camera.vmt
        • npc_combine_camera.vtf
        • npc_fastzombie_torso.vmt
        • npc_fastzombie_torso.vtf
        • npc_fisherman.vmt
        • npc_fisherman.vtf
        • npc_helicopter.vmt
        • npc_helicopter.vtf
        • npc_ichthyosaur.vmt
        • npc_ichthyosaur.vtf
        • npc_sniper.vmt
        • npc_sniper.vtf
        • npc_stalker.vmt
        • npc_stalker.vtf
        • npc_strider.vmt
        • npc_strider.vtf
        • npc_turret_ceiling.vmt
        • npc_turret_ceiling.vtf
        • npc_turret_floor.vmt
        • npc_turret_floor.vtf
  • settings/
    • mount/
      • hl2-episode-1.txt
    • npc_spawn/
      • npcs.txt
      • weapons.txt
    • spawnlist/
      • hl2_episode_1_models.txt
      • hl2_lost_coast_models.txt
• Totsters_Extra_NPC_Addon.PNG

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