Hybrid game
Begin a game with the hl.exe -dev -console -game action command line. This will enable the console window. You can now go into the original Half-Life missions with Action Half-Life's weapons and models. The scientists, aliens, and Barneys are the same and are really fun to kill. When you go into the single player mission, display the console window and type sv_cheats 1 to activate cheat mode. Then, type /god for God mode, /impulse 101 for every weapon, /noclip to fly around through anything, and /notarget for everything to ignore you. Note: The game will crash in time.