Atomic Bomb!

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
          • atomicbomb <-- Addon folder!
            • e.g.
            • lua
            • maps
            • materials
            • models
            • etc

• atomicbomb/
  • info.txt
  • lua/
    • entities/
      • sent_atomic_bomb/
        • cl_init.lua
        • init.lua
        • shared.lua

batataninjaflamejante, kevinbhunjunr1, tonnum321a, CedaZmaj, slv28, alanignat, sartit_nbr, SANS:v, MOJO JOJO, bynyjbybyn39, taidepzai986, BMW_THEMLG, coman_cosmin2004, NOT FINI, piltan1383, kel, porrr8405G4Skins.com, DexoPapuORG, benjamin_azemi, cmlamorte, t_mason, yks):, aneta.korzeniowska, guillaume.colasse, now you die!, KVAK, narayanbehera503, caspianff, draszer, yittik.time78, kuruczzoltan2006, Buzz_Rakeťák, Menockcidez, lubbevaughan8, Long Haul, giorno, dragon12345h, Letsgame38, bartosz.gra, MADCAT205, sirawit4129, Gauzyオッパイ, shibashuster058, brandonbarr975, Ready... Glow ESP + Aimbot+ Wall, tazmania55, Inter, taty.soulivanh54, hawky232, DatLukeDoe +1689 others