MORE HALF-LIFE: OPPOSING FORCE ALL-STARS REVEALED

Bellevue, WA (September 10, 1999) - Sierra Studios, Gearbox Software and Valve are proud to announce four additional members of the industry "All-Star" team designing the multiplayer portion of the upcoming PC title,
Half-Life(tm): Opposing Force(tm), the entirely new episode for the Game of the Year.

The four veteran designers announced today are: Richard "Zdim" Carlson, David "Kevlar" Kelvin, Marin "Kandyman" Gazzari, and Eric Reuter. They join the team along with Richard "Levelord(tm)" Gray, who announced his participation earlier this summer.

"Gearbox is obviously very excited to be working with such an amazing team of talented designers on Op For," says Randy Pitchford, co-founder and lead game designer at Gearbox. "It also adds a degree of suspense
as we are waiting just as anxiously as everyone else to see what kind of amazing maps they put together for us to play."

About the All-Stars:

Richard "Zdim" Carlson
Growing from being one of the most respected amateur designers of the Doom and Heretic era, Carlson defined unique black and white sections of Ion Storm's upcoming epic RPG Anachronox. He then contributed to John Romero's Daikatana before making the move to Looking Glass Studios where he is a pivotal designer for the upcoming Thief 2.

David "Kevlar" Kelvin
Aside from being a very visible member of the early 3D level design community, Kelvin was a member of Team Evolve creating several missions for the Quake II Zaero pack. He spent a short time at Monolith contributing maps for Blood II and Shogo before joining Legend Entertainment where he has shipped Unreal: Return to NaPali and is currently working on Wheel of Time.

Marin "Kandyman" Gazzari
Austrian Marin Gazzari is probably the most respected deathmatch level designer of the era. His simple yet perfectly flowing designs have been the setting for countless tournament and clan matches. Although he is probably best known for his work with Quake's ZerStoerer pack, his "kndy" series of deathmatch maps are among the most played maps ever created.

Eric Reuter
One of the most accomplished designers of the Opposing Force "All Stars," Eric is currently the lead level builder of Unreal PlayStation which will offer a completely new single player episode. Eric was a designer with
the original Unreal team after working with 3dRealms on Shadow Warrior. Eric became a professional designer after his early level work for Doom found its way into the SAM'S published books "Tricks of the Doom
Programming Gurus" and "3D Game Alchemy."

Half-Life: Opposing Force (a.k.a. Op For) will feature over one dozen new multiplayer levels created by 3-D action industry All Stars. Op For also features an expansive new single player episode were players return to
the Black Mesa Research Facility from the exciting new perspective of a soldier to eliminate a new breed of fierce aliens. The title, which is being developed by Gearbox Software, is on schedule to ship this fall.

Founded in January 1999, Gearbox Software is a team of veteran 3D game developers collected in Dallas, Texas. The Gearbox crew is made up of artists, designers, and programmers who joined forces to form their own development house after stints at a variety of companies, including 3D Realms, Microprose and Ritual. Half-Life: Opposing Force is scheduled to be the first offering from this talented new studio.

Founded in 1996, Valve develops entertainment software. Half-Life is Valve's debut title. Since its release in November, 1998, Half-Life has won more than 45 game of the year awards from publications that include PC
Gamer, Computer Gaming World, and Cnet's Gamecenter. Valve's upcoming title, Team Fortress 2: Brotherhood of Arms recently won the E3 Game Critics' Award for Best Action Game and Best Online Game. More information about Valve is available through the company's web site at www.valvesoftware.com.

Sierra On-Line, Inc. is one of the original developers and largest worldwide publishers of interactive entertainment and productivity software. Sierra, a division of Havas Interactive, is comprised of a family of brands: Sierra Attractions(tm), SierraHome(tm), Sierra Sports(tm), Sierra Studios(tm), and Dynamix(tm), a Sierra Company. Havas Interactive holdings also include Knowledge Adventure(r), Blizzard Entertainment(r) and WON.net(tm).

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