In this particular game, designed in first person shooter format, the player has to advance through several puzzles and tasks. Puzzles are not the only hindrances, but do unseen Gordon places many obstacles. There are instances where the player gets to kill the enemy, which makes the game fall into the category of Killing games. The enemies to be eliminated include a number of aliens such as, bullsquids, headcrab zombies, and Vortigaunts. Shooting through the obstacles, the player is also assisted by a handful of non player characters especially guards and scientists. The wide array of weapons availed in this shooting game are mostly unique with the crowbar tau cannon, Gluon cannon filling the pack. The gun game also features the application of a variety of guns such as Glock 17 pistol, Sniper Games, MP5 submachine gun with an attached grenade launcher, Colt Python .357 Magnum revolver and lot more. Set in a remote desert area of Mexico, the game features the struggle of Dr. Freeman to get out of the ruins of a terribly wrong experiment that ultimately got caught in between the Aliens and the US Marine Special Forces. Along with the surviving population of scientists and security guards, he finds way to the success. The Shooting games online have provisions for free downloading of the above said game.