Gordon Freeman, a human scientist who was at the center of events that took place shortly before the rise of the Combine, awakens from his stasis and is inserted into a train to City 17 by the mysterious G-man. He soon becomes part of a resistance group and makes an attempt to bring down the Combine and liberate the Earth.
The player guides Gordon Freeman through City 17 and the wilderness that surrounds it, encountering friendly characters and fighting dangerous foes along the way.
Half-Life 2 is a linear first-person shooter with light puzzle-solving elements and many setpieces. The game features a realistic physics system: Gordon can pick up objects and toss them freely, and many of the puzzles are physics-based.
Gordon's enemies include Combine forces, which utilize various firearms, gadgets, and vehicles to hunt him down. To defend himself, Gordon has a range of weapons available, including the iconic crowbar for close-quarter fighting and grenades. The gravity gun is also notable, allowing Gordon to pick up objects and hurl them at the enemy with great force.
Setpieces in the game include coordinated assaults on enemy bases, fighting gigantic boss enemies, bringing down aircraft with the rocket launcher, and others. The player must navigate buggy-type vehicles and summon an army of antlions to unleash on unsuspecting foes.
The game comes with Half-Life 2 , a version of Counter-Strike: Source made with the new Source engine, and Half-Life 2: Deathmatch , an online multiplayer game featuring the same physics and weapons as the single player game.