Half-Life (2002)

Half-Life, stylized as HλLF-LIFE, is a science fiction first-person shooter developed and published by Ubisoft. The player takes the perspective of the scientist Gordon Freeman who struggles to escape an underground research facility after a failed experiment causes a massive alien invasion through a dimensional rift. Designed initially for Microsoft Windows and later brought to other platforms such as Original XBOX and OS X, the game uses a considerably modified version of the C&C Renegade engine, called W3D.

Plot
The time is 8:47 AM -- Dr. Gordon Freeman is late for work. The 27-year-old MIT graduate rides the tram to the Sector C Test Labs and passes Barney Calhoun, seen bashing on a locked door. As he nears the Anomalous Materials Laboratory, Gordon can see nuclear missiles ready for transport to launch sites, robots nearly crashing into the tram, and the intricate workings of the Black Mesa Research Facility revealing themselves as being fragile, and more often than not, broken.

The public announcement system announces the most recent news, making ironic comments about healthcare measures on radiation and urinalysis tests, as large pools of radioactive waste pass beneath him. At a Loader crossing, the tram is stopped, and on the left, a mysterious man in a suit is waiting in another stopped tram. Eventually, Freeman's tram reaches its destination and, after stepping out onto the catwalk, his day begins.

Arriving at the Anomalous Materials Laboratory, Gordon is informed by a security guard of several messages for him that were lost due to a system crash, and is told to get into his HEV Suit and head down to the lab, where he finds himself face to face with the people conducting his test; they inform him that they have a unique and large sample of a classified origin and that they will be deviating from normal procedure to accommodate for this.

Once in the test chamber, he goes to the control panel and presses the button to start the rotors on the Anti-Mass Spectrometer. Rising up from the delivery system, the sample arrives and Gordon proceeds to push the cart into the Spectrometer's beam, upon contact with the sample a Resonance Cascade event occurs, causing Alien organisms to teleport to the surrounding Facilities and sending him to a strange alien world where he passes out.

Gordon regains his consciousness inside the destroyed Test Chamber, looking for a way out he notices the whole facility around him has received massive structural damage, most of the personnel is dead, and aliens begin to teleport into the facility. After being told that all phones are out, Gordon is requested by one of his colleagues to try to make it to the surface in order to acquire help.

Starting his journey, Gordon finds a Crowbar to help him get past obstacles, and since the Tram System is too damaged to work, to find a way out he must cross the Sector B Coolant Reserve Facility, now overrun with alien creatures, occasionally witnessing the mysterious suited man from earlier watching him from out-of-reach places, always walking off before Gordon can get to him.

Gordon reaches the administration center at Sector D, where several Scientists and Security Guards are barricaded into the office complex, hiding from the alien creatures. Avoiding the facility's Ceiling Turrets and the invading Vortigaunts he hears from the personnel that the military have arrived to rescue the people trapped but that he should still head for the surface.

Reaching the High Security Storage Facility at Sector D, Gordon learns that the way out is through the Silo D door, but to open it he must round the facility to the Silo door's control room. Passing through the storage area and avoiding the Sentry Turrets, Gordon witnesses the soldiers killing the scientists on sight. The soldiers, known as the Hazardous Environment Combat Unit, were coming, not on a rescue mission, but on a total cover-up mission. As such, they are not just killing the aliens, but also targeting everyone associated with the resonance cascade in order to contain the incident.

When he eventually reaches the surface, Gordon finds the facility under total control of the HECU and in the middle of an artillery bombardment. Taking cover, he is forced back into the underground complex, finding his way into the silo door's control room where a scientist informs him that, if anyone can end this catastrophe, it is the science team in the Sector F Lambda Complex, located at the opposite end of the facility, but to get there, Gordon must find the old, decommissioned rail system beyond the Silo complex.

With access to the Silo D, Gordon mounts the old tram system to get to the Rocket Test Labs, a largely sealed-off area of Black Mesa dating back to its earlier days as a missile complex, now being used as a dumping ground for toxic waste from the rest of the facility, where the HECU soldiers have yet to get a good foothold due to the overwhelming amount of aliens and toxic waste in the area.

Arriving at the Rocket Test Silo, Gordon is warned of the Tentacles, a large alien creature blocking his way, and is instructed to fire the rocket engine to kill it before it keeps growing. But to fire the rocket he must first turn on the oxygen and fuel pumps as well as the power generator, after which Gordon is able to kill it by using the rocket engine to incinerate it. This uncovers a way out through the meters-deep dirt tunnel dug by the Tentacles, leading Gordon closer to Sector E's Materials Transport.

Trying to reach the surface once more, Gordon's progress is thwarted by a Gargantua in the Sector E Materials Transport. He then learns from a dying security guard that if he restores the generator, he can ride the tram to the surface.

Freeman enters the Houndeye infested subterranean areas and activates the generator, restoring power to sector E; after activating more switches, he destroys the Gargantua patrolling the area by turning on the transformers supplying the rail system with power. It is also possible to kill the Gargantua using an excessive amount of explosives.

Jumping onto a tram, he is able to continue his way by smashing through the concrete barricade blocking the access to the rail system.

As Gordon rides the tram into the Materials Transport section of Black Mesa, he learns from a security guard that he must ride to the High Altitude Launch Center to launch a satellite, which the Lambda Team can use to reverse the effects of the Resonance Cascade.

Freeman also discovers the HECU's true hatred for him, as well as their larger reinforcements: sandbag bunkers with rapid-fire sniper rifles, mounted machine gun turrets (manual and automated), and even mounted rocket launchers.

After going round in circles for a while, Gordon goes up several elevators and at last reaches the surface again near the launch site; he sends the rocket up into orbit and goes back underground.

Continuing towards the surface, Gordon encounters a terrifying new aquatic Xen creature, the Ichthyosaur, and acquires a deadly new weapon to fight it. After an underwater battle with an Ichthyosaur, he manages to escape and get back on his way.

After battling with the Black Ops, another military crew trying to eliminate even the HECU, Freeman is captured by two HECU soldiers. Instead of taking him in for questioning, out of spite, they remove all of his weapons and drop him in a trash compactor.

After escaping from the trash compactor and getting back to the surface, Gordon stumbles towards a mostly abandoned part of the facility, meant for processing and disposing of waste and hazardous materials.

Dodging and jumping through antiquated compaction machines, large vats of waste, and slipping through furnaces, as well as riding on gravity-defying conveyor belts, Freeman leaves this part of the facility.

Gordon eventually winds up in a secret part of the facility where he discovers that scientists had been "collecting" specimens from Xen since long before the incident occurred.

Inside, Freeman continues to rearm himself to rejoin the battle against the HECU. He also meets the alien military units, the Alien Grunts; and finds one of the most powerful weapons in the facility, the Tau Cannon. Soon, he heads outside to search for the Lambda Complex.

Gordon again reaches the surface, which is now a war zone. The Vortigaunts, along with Alien Grunts and Gargantuas, have begun making determined attacks against the Marines, and the tide of the battle is beginning to turn in favor of the aliens; the Marines call in reinforcements, but it is not enough. Gordon must scale cliffs and navigate the bombed out buildings while avoiding both sides.

Many skirmishes are seen between the HECU and the Xen forces. Finally, Gordon reaches relative safety underground.

The HECU determines that they are fighting a battle they cannot win against the Xen aliens. With this, as well as having continually failed to neutralize Freeman, they abandon their mission and begin to evacuate the facility, calling in air strikes and heavy artillery to cover their retreat.

Gordon enters an underground storage garage to avoid the bombardments, and eventually fights his way through scores of aliens and several groups of the decimated HECU forces before reaching the Lambda Complex.

After much struggle, Gordon finally reaches the Lambda Complex, which he discovers to be the place where Black Mesa developed the teleportation technology that allowed scientists to travel to Xen in the first place.

The handful of surviving personnel, who have held themselves up in a small stronghold, inform Gordon that the satellite he launched earlier was not able to reverse the effects of the Resonance Cascade because an immensely powerful being on the other side is keeping the rift between the worlds open, and Gordon must go to Xen to kill it and prevent the aliens from taking over completely.

Before being teleported to Xen, Gordon gains access to an arsenal, health and HEV-charge caches, and is finally given the Long Jump Module. After an attempted interception by Alien Controllers, the scientists open a portal and Gordon jumps in.

Once in the border world of Xen, Gordon encounters many of the aliens that had been teleported into Black Mesa in their natural habitats, as well as the remains of some HEV-wearing researchers who came before him. In order to progress, he needs to re-activate a portal inside one of the floating islands to venture more of Xen's perimeters.

Freeman is made to face one of the Nihilanth's most powerful minions; the Gonarch, found in its lair, located in another floating island. Gordon is able to kill it and use the portal created after its death to continue.

Gordon's journey across Xen continues, but his supplies are running short, spent on destroying the Gonarch. He is teleported to an Alien Grunt cloning facility, where the army of Xen is created. There, Gordon finds a group of docile Vortigaunts working, before exiting the facility and getting ready to enter one last teleporter.

In a vast cave, Gordon finally confronts the powerful and mysterious being that is holding the portal open, the Nihilanth. Gordon destroys its healing system, allowing him to destroy its vulnerable brain. As the creature dies, it floats toward the ceiling, emanating portals, and finally exploding in a giant green blast that overpowers Gordon's senses.

When Gordon comes to his senses, he finds himself in front of the G-Man. Both are transported to various locales around Xen, while the G-Man praises Gordon's actions in the border world, to later explain that his "employers" have agreed that Gordon has "limitless potential," and have authorized him to offer Freeman a job.

The G-Man and Gordon are teleported a last time to a tram car, flying through space at immense speed. By stepping into a portal, and knowing that his only other choice is a battle he has no chance of winning, Gordon accepts the G-Man's offer.

Finding himself floating in nothingness, he hears the G-Man's voice one last time; "Wisely done, Mr. Freeman, I will see you up ahead..."