Half-Life 2: Episode Two

Half-Life 2: Episode Two is the second installment in a trilogy of episodes for the 2004 first-person shooter computer game Half-Life 2, from Valve Corporation.

Continuing with Valve's method of orienting each episode around a particular theme or set of technologies, Episode Two focuses on expansive environments, travel, and large, nonlinear battles. Following the closing events of Episode One, it sees Gordon Freeman and the series' other major characters moving away from City 17 to the surrounding wilderness.

The first two episodes of Half-Life 2 were developed concurrently by separate teams. Episode Two was originally intended to be released in two different packages: the "Black Box" – which was to ship for the PC only, and was to contain Episode Two, Portal and Team Fortress 2 – and the "Orange Box" – which was released for the PC, the XBOX 360 and the PS3, and contains all the Black Box games in addition to Half-Life 2 and Episode One. The Orange Box is now available at retail stores and on Valve's Steam content-delivery system, however, the Black Box was cancelled. Instead Valve introduced a gift feature to enable those who already own Half-Life 2 and/or Episode One to give the extra copies they buy in the Orange Box away as gifts. It is possible to buy one or all of the Black Box games separately on Steam, but even if Half-Life 2 and Episode One are already owned, the Orange Box is still cheaper than buying all three games individually.

Characters

 * Gordon Freeman
 * Alyx Vance
 * Vortigaunts
 * Eli Vance
 * Isaac Kleiner
 * Arne Magnusson
 * Judith Mossman
 * G-Man

Enemies

 * Xen Aliens
 * Antlion
 * Antlion Guard
 * Antlion Worker
 * Barnacle
 * Fast Headcrab
 * Fast Zombie
 * Headcrab
 * Poison Headcrab
 * Poison Zombie
 * Zombie
 * Zombine
 * Combine Forces
 * Combine Advisor
 * Combine Dropship
 * Combine Gunship
 * Overwatch Soldier
 * Overwatch Elite
 * Hunter-Chopper
 * Hunter
 * Manhack
 * Strider

Gameplay
As was suggested in press releases, Episode Two generally concentrates on more expansive locales as compared to the claustrophobic Episode One, particularly in its latter chapters, although it ends similarly to Episode One with a pitched battle in a fixed environment. The Muscle Car chapters are very reminiscent of the Highway 17 Chapter of Half-Life 2. Episode Two is longer than Episode One, approximately two thirds the length of Half-Life 2.

Episode Two introduces two new enemies: the Antlion Worker and the Combine Hunter synth. As discussed in the commentary of the game, both display new, sophisticated types of A.I.: the Antlion Workers' in their standoffish approach, and the Hunters' intelligent flanking and flushing out maneuveurs. With the Hunters in particular, with their resistance to conventional attacks, their deadly close combat moves and their weakness to thrown objects, the developers hoped to encourage players to interact with the game environment more closely, and try different tactics each time.

The game also introduced Antlion Grubs and Antlion Workers, the behaviour of whom make the first chapters of the game different from anything yet experienced in the Half-Life games, and were also used to explain the inner workings of Antlion society. The game also gradually reveals the characteristics of the sinister Combine Advisors, and they play a much more central role to the Episode than in previous installments.

Although no new weapons as such are introduced, the Strider Buster, used to defend White Forest against a Combine offensive, is crucial to the last stages of the game. Valve stated before the release that they were not interested in creating new weapons, as they were more interested in exploring every dimension of the Gravity Gun, the Strider Buster being the outcome of this. This decision came in spite of the fact that the lack of new weaponry in Episode One was one of its most criticised aspects.

Technical Information
Running on the so-called "Source 2007" version of the Source engine, Episode Two comes with numerous technical improvements and new features as well as those introduced in Episode One (such as Phong shading and HDR lighting). Some of the more important technical improvements seen in Episode Two are:


 * Cinematic physics - where real-time physics calculations are mixed with keyframe animation targets to create large-scale physics events. The bridge collapse at the very beginning of Episode Two is one example, as are the collapsing buildings in the final battle.
 * Motion blur
 * Dynamic lighting and shadowing 2
 * Soft-Particle system
 * Dual and quad-core CPU optimizations

In addition to the widely-publicised new features, there are also a number of less noticable but nonetheless significant improvements. Lighting effects have been improved even further since Episode One, with the bloom effects toned down slightly to give the game a slightly less surreal look. Many character models have been improved upon once more, while the A.I. is slightly more sophisticated, most noticeably in the behaviour of the new enemy - the Hunter synth. Most textures have been improved, special shaders have been applied to many characters and objects and almost everything is bump mapped.

Soundtrack

 * "Extinction Event Horizon" - 2:03
 * "Vortal Combat" - 3:15
 * "Nectarium" - 1:47
 * "Crawl Yard" - 1:11
 * "Hunting Party" - 3:29
 * "Shu'ulathoi" - 2:36
 * "Sector Sweep" - 2:47
 * "No One Rides For Free" - 1:02
 * "Eon Trap" - 3:14
 * "Inhuman Frequency" - 1:49
 * "Abandon In Place" - 2:45
 * "Last Legs" - 2:07
 * "Dark Interval" - 1:33