Team Fortress Classic

Team Fortress Classic (TFC) is a popular multiplayer mod for the first-person shooter computer game Half-Life that allows teams of players to compete on the Internet in action packed games of capture the flag, escorting a VIP, territory control, and many other missions. It was ported to Half-Life by the developers of the Team Fortress mod for Quake in collaboration with Valve Software.

Classes
After choosing a team (i.e., the red team or the blue team) and before respawning, players must pick a "class." Each class has its own unique strengths and weaknesses, which are offset by other classes. The interdependence between the various classes represents the foundation of TFC. For example, the Scout is the fastest class in the game, but has weak armor and weaponry. The Heavy Weapons Guy (HWGuy) has deadly firepower and massive armor, but is the slowest class. Despite his heavy armor, an unsuspecting HWGuy can be quickly killed with a backstab from a disguised enemy Spy, but a Scout can remove the Spy's disguise, and the HWGuy can provide very effective support fire for a Scout trying to escape with the other team's flag. As such, TFC's class-based structure creates a Rock, Paper, Scissors dynamic wherein each of the classes offer important counters to each other. This section describes the strengths and weaknesses of each class:

Scout
Weakly armed and armored, the fast-moving Scout is best suited to flag-capturing and little else. With a touch, this class strips an enemy Spy of its disguise and disarms a Demoman's detpacks. The Scout is armed with crowbar, single-barreled shotgun, nailgun, up to 3 caltrops and concussion grenades. Skilled Scouts who master the technique of conc jumping are able to navigate maps very quickly and are very hard to catch.

Sniper
Armed with the deadly sniper rifle, this class employs one of TFC's rare "instant kill" weapons (the only other two being the Spy's knife and the Demoman's detpack) and the game's most powerful ranged weapon. Equipped with a scope, this weapon is extremely accurate due to its ability to zoom and strike opponents instantaneously. As potent as the sniper rifle is in the hands of an experienced player, it has its drawbacks. Specifically, a slow "charge-up" time (it takes about 8 seconds of holding the fire button down for the shot to have maximum impact) and the "tunnel vision" vulnerability while zoomed in, which greatly reduces the player's peripheral vision and awareness. This is exacerbated further if the shooter is set ablaze by the Pyro's weaponry, or concussed, rendering an accurate shot nearly impossible. Furthermore, the sniper gun has a visible laser sight which can give away the Sniper's position if he isn't careful and he can neither fire it while running nor while in the air. This class works best from concealment; with only average armor, health, speed, and with weapons unsuitable for sustained firefights, an exposed Sniper rarely lasts long. The sniper rifle has an "autorifle" mode that combines the weapon's accuracy with a rapid rate of fire, but this mode quickly exhausts the limited rifle ammo. His other weapons consist of the crowbar, nailgun, and fragmentation grenades (up to 4). His special skill activates the sniper rifle's scope.

TFC maps often feature prominent and easy-to-find "sniper decks" whose occupants are highly exposed, thus compromising the Sniper's best defense: stealth. Nevertheless, most Snipers have no choice but to use these locations, making them easily located and targeted by the opposing team.

The amount of Snipers allowed on a given server is often limited for a number of reasons, but mainly because this class can be so deadly by itself, it doesn't lend itself to using teamwork. "Sniper wars" tend to develop, which can detract the game objectives for other classes.

Soldier
The Soldier (sometimes shortened to solly) is the mobile artillery of TFC. Combining ample armor (second strongest behind the HWGuy) with high mobility and very effective weapons, this well-balanced class is both favored and resented. The Soldier's primary weapon, the rocket launcher, packs a deadly explosive punch, but requires a degree of skill to use effectively. Since the rocket projectile takes time to arrive at its destination, fast-moving opponents can usually avoid a direct hit, especially at long range. The most proven tactic is to get within short range and aim at the feet of the target, rather than directly at it, letting the radius damage of the explosive (termed "splash damage") do the work. This has the additional effect of "bouncing" the victim, sometimes knocking them off narrow walkways, and inhibiting their aim. Skilled players utilize this advantage even further; by firing at the feet of their opponents with the right angle and timing, they can immobilize the opponent while inflicting damage. The opponent is launched vertically into the air, only to receive another explosion right before they land launching them into the air again. This can go on until the Soldier has to reload or the opponent is dead. This is especially devastating against Snipers, who cannot fire their main weapon without both feet on the ground. This "splash" nature of the RPG provides another big advantage to the Soldiers, rocket jumping, allowing the normally slow moving class to cover ground very quickly, and reach areas otherwise inaccessible, at the cost of a self-inflicted loss of health and armor. As effective as the rocket launcher is, it can only carry four rockets at a time, which can be expended very quickly in a heated battle. A skilled player reloads early and often, (ideally between enemy encounters) and knows when to switch between the RPG launcher and the Soldier's 2nd best friend, the double-barreled shotgun. While of limited use at longer ranges, at close range the so-called "super shotgun" is very deadly.

Another weapon unique to this class is the nail grenade, which, when thrown, releases a stream of nail-like shrapnel horizontally in a 360 degree radius, damaging all in its path before exploding. The Soldier spawns with two of these, as well as a maximum of four normal grenades, the super shotgun, single-barreled shotgun and the standard crowbar.

Demoman
Arguably the most difficult class to master, the Demoman's weapons are a challenge to use, but in the hands of a skilled player, this class can single-handedly decimate the other team. The Demoman's primary tool is the grenade launcher. This weapon can hold up to 6 grenades, which behave differently from the game's regular grenades. Rather than relying on simple fuse detonation, the Demo's grenades arm nearly as soon as they are launched, and explode on contact with an enemy, or after a few seconds. The Demoman can also choose to fire pipebombs from this weapon (a maximum of 8 at a time), which do not detonate on impact, but rather are triggered; either by the Demo's "special skill", or a few minutes after being deployed. They also detonate if the player is killed, or if they are within the blast radius of an Engineer's EMP grenade.

Similar to the Soldier class, the Demoman can perform a special type of jump with his pipebombs. By placing a pipebomb on the ground, then jumping over it while detonating it, the Demoman can perform a jump greater in height than a Soldier's rocketjump and greater in distance than a conc jump. The downside is that any more than two pipebombs will severely damage the Demoman.

The ability of a Demoman to deliver a large volume of explosive death nearly anywhere makes this class very valuable on defense, as well as clear enemy fortifications, or temporarily deny an area to aid the offense. In fact, certain maps require a Demoman to use his detpack (a large, extremely powerful, timed bomb that instantly kills anyone in the area) to open (and sometimes close) alternate entryways, or destroy key map objectives. The detpack can also be set to explode at timed intervals of 5, 20, and 50 seconds.

The main weakness of this class is its inability to deal with long range threats. Additionally, there is a degree of unpredictability with the grenade launcher, as the grenades sometimes bounce unpredictably and the launcher's relatively slow reload time can leave the Demoman unarmed.

Another important component of the Demoman's arsenal is the MIRV grenade. These potent grenades explode twice, the first explosion sends out 4 submunitions, which explode again to devastate a wide radius. Armed with 2 MIRV grenades, up to 4 normal grenades, the single-barreled shotgun, and the crowbar, this class is fairly fast and wears better than average armor, making it capable on defense or in an offensive support role.

Medic
The most powerful of the light classes, the Medic is armed with a medkit, single and double-barreled shotguns, a "super" nail gun, and up to 4 normal grenades and 3 concussion grenades.

He also has decent armor, the second highest speed, and great mobility. However, he is vulnerable to the Soldier's rockets, unless relying on grenades. Despite his profession and the bright red cross on his chest, he is the offense in clan matches. Like the Scout, he can also concjump (see conc jumping).

The medkit has several uses. It automatically heals the user over time with two health points every two seconds. When used on a team member it cures all injuries, and boosts health, even raising it past the maximum to provide a bonus that gradually fades back to full health. Using it on an enemy gives him a contagious infection which slowly reduces their health. Furthermore, this infection can be spread to other players on contact and can only be cured by that team's Medic. Medics, however, are immune to infection. This is a good class for new players to learn the game's basics.

HWGuy
Often referred to as the tank of TFC (or sometimes the less endearing "fatty" or "HWGay"), this class is extremely slow, but well armored, and very deadly. While firing his fearsome Minigun (or Assault Cannon/AC), the HWGuy moves even slower, but is able to cut down even the most heavily armored classes in seconds. The AC's devastating damage output is countered by notable drawbacks: it takes a few seconds of "windup" before it begins firing (allowing fast-moving classes to slip past), it consumes ammo at an alarming rate, and it is very inaccurate when used at longer ranges. His slow speed and his inaccurate weapon make the HWGuy a sitting duck out in the open. Furthermore, skilled players are often able to circle-strafe inexperienced HWGuys to death. Larger maps limit the effectiveness of the slow-footed HWGuy, but this class is a force to be reckoned with when holding down a defensive choke point, or providing cover in an offensive support capacity. The HWGuy also spawns with the crowbar, single and double-barreled shotguns, 2 MIRV grenades and up to 4 normal grenades.

Due to the simple "point and kill" nature of his weapons and his high survivability, this is an excellent introductory class for new players to learn the game's basics.

Pyro
The Pyro class is something of an enigma in TFC. Relatively well-armored, and faster than all but the lightest classes, the Pyro is much-maligned for his less-than-deadly weaponry. Experienced players recognize that the Pyro is without peer in using his primary tools: frustration and confusion, as demonstrated by his main weapon, the flamethrower. Although having a short range, the Pyro carries a large ammunition reserve, and can pump out a steady wall of flames nearly indefinitely. These flames are difficult to see through, making it hard for enemies to draw a clear bead on a streaking Pyro. The flames deliver moderate damage while in direct contact, as well as igniting any enemy it touches, causing additional light damage over time until the flames are extinguished either by (1)contact with water, (2)a friendly Medic's medkit or (3)time. Furthermore, ignited players have to suffer with flickering flames obscuring their view, compromising their ability to aim and navigate. This is especially debilitating for the Sniper, making this class an ideal counter to them. Some players are so disinclined to risk of being ignited that they avoid Pyros entirely, similar to the aversion to being infected by an enemy Medic.

His secondary weapon, the incendiary rocket cannon (or IC) is similar to the Soldier's RPG, except the IC rocket is much slower moving, causes significantly less damage on impact (although it has a broad igniting effect where it hits, even through narrow walls or floors), and doesn't suffer from the RPG's restrictive ammo limit.

Due to its relative lack of lethality, the Pyro is effective (but not dominant) as either assault or defensive support, softening up a defense for stronger, slower classes to finish off or for lighter, faster classes to slip past, weakening and distracting incoming attackers, or generally being a disruptive force. Its greatest weakness is its susceptibility to the Engineer's EMP grenades, the bane of the Pyro. Virtually all of the ammo a Pyro carries is highly vulnerable to the EMP blast, creating an explosion powerful enough to kill not only the Pyro, but also any nearby teammates. This class also lacks any significant ranged attacks, making it susceptible when caught out in the open.

The Pyro also carries 4 unique napalm grenades, which create a temporary field of flame, igniting any enemies passing through its area of effect. It also spawns with up to 4 normal grenades, the single-barrel shotgun and the crowbar.

Spy
The stealth assassin of TFC, this class has fairly light armor and average speed, but has the unique ability to disguise himself as a member of an opposing team. His "special skill" button brings up the disguise menu, letting the player choose what team and what class he would like to appear to be. Enemy sentry guns will not fire on a Spy disguised as a member of that team, making them very capable of penetrating a base's defense. A disguised Spy can also position himself behind an unwary enemy to deliver an instant-kill stab (in the back of the head) with his knife. Attacking with the knife or firing any weapon causes the Spy to lose his disguise, but tossing grenades does not, making Spies ultimate sentry gun killers. The Spy can also feign death, letting him bide his time as a corpse while he changes disguise and plans his next move. Geared more for offensive support, the Spy is one of the most challenging classes to play effectively, but a skilled Spy can be very disruptive against the enemy team. Even suspicion of a Spy in the enemy team's midst can create a gaping hole in an organized defense, as defenders waste ammo shooting each other for "Spy checks" (enemy Spies still visibly bleed if damaged) or are lured out of position. However, this class lacks the speed, armor, and weaponry to hold in a straight-up shootout against most other classes, and any contact with an opposing team's Scout or Spy will expose him.

Another potent weapon available only to this class is the gas grenade, which has a temporary hallucinatory effect, causing enemies to see and hear phantom explosions, shots, flames and tossed grenades for a short period of time. This relatively harmless effect masks the fairly moderate damage over time the grenade causes while an enemy is in its area of effect. In large doses, Spy gas (or Fairy Dust) can cause severe damage.

Rounding out the Spy's unique arsenal is the tranquilizer pistol, which fires a special dart that does negligible damage, but greatly reduces its target's rate of movement temporarily. It's best used on faster classes to facilitate a lethal knife strike. The Spy is also armed with the double-barreled shotgun, nail gun, and up to 4 normal grenades.

Engineer
Having only average speed and the second lowest armor and health, the Engineer isn't well suited for gunning it out; however, he more than makes up for his shortcomings with his special ability to construct a sentry gun (SG), a stationary automated weapon that targets any enemy players it can detect, unleashing a hail of firepower at them. With a well placed SG, an Engineer forms the backbone of a team's defense, able to defend two points at once. Once built, a so-called "level 1" SG consists of a turreted machine gun, which is somewhat slow to lock on to enemies, inflicts fairly light damage and is easy to destroy. It can be "upgraded" by any Engineer of the same team who hits it with his spanner (at the cost of 130 cells) to a level 2 SG. This replaces the single-barrel machine gun with a HWGuy-style chaingun, making it very effective at cutting down lighter classes and increases its range and durability. The SG can be upgraded yet again to level 3, which adds a second chaingun and a powerful rocket launcher to the mix, and another increase to range and durability. A level 3 SG can outslug even a heavily armored HWGuy under the right conditions.

As powerful as it is, the SG does have drawbacks. It only locks onto enemies that pass within its detection range, and it only sweeps an area of approximately 270 degrees, creating potential blind spots that can be exploited, especially if it is not well-placed, or if the other team stays beyond its limited range. It cannot detect disguised Spies at all, who can safely bombard it with grenades. It rapidly consumes ammo, requiring near-constant trips to resupply areas, leaving it unguarded and vulnerable. Proper placement and maintenance of an SG is crucial to the Engineer's effectiveness.

In addition to the SG, this class can also construct:


 * One-way teleporters - Ring shaped devices that teammates can use for quick jumps across larger maps. The first teleporter an Engineer builds is the "entry pad", and the 2nd is its "exit pad". Opposing players cannot use them. They are fairly fragile and generate a distinct noise when activated, thus opposing teams are usually quick to find and destroy them.


 * Ammunition dispensers - Stationary machines that slowly generate ammo of all types, and can be used by any player &mdash; friend or foe. When a player touches an enemy dispenser, it sends an alert to its builder. For this reason, dispenser are sometimes more useful as a perimeter alarm. An Engineer can also detonate his dispenser at any time, causing incredible damage if the dispenser is fully loaded.

In order to construct the above items the Engineer requires cells converted from armour pickups or standard ammunition packs scattered around the map. The Engineer must make frequent trips to ammunition caches in order to upgrade sentry guns or re-stock ammunition dispensers. Teammates often support their Engineers by tossing unwanted ammo to them whenever possible.

Aside from the SG, this class carries another of the most fearsome weapons in TFC – the EMP grenade. This potent weapon does not explode itself. Rather, it detonates the cell, rocket, and shell ammunition of any enemy within its area of effect, approximately 15' radius, including through narrow walls and floors. This makes the EMP extremely deadly to classes that rely on cell ammo, such as the Pyro and Demoman, but is also effective against Soldiers and HWGuys. The explosive damage caused by closely-clustered foes is often enough to decimate the entire group at once, even the lighter classes, who would otherwise not be particularly vulnerable to the EMP.

An Engineer can repair teammate's armor, or any other Engineer teammate's SG, teleporter, or dispenser by hitting it with his spanner. This class spawns with up to 4 normal grenades, and is also armed with a double-barreled shotgun and a "railgun" (not to be mistaken for the Q3A weapon of the same name) that fires slow-moving green projectiles. While weak against normal opponents, this weapon has infinite range and is effective against sentry guns.

Civilian
Only found in "VIP escort" type maps and other special modes. A weak, slow speed character armed with just an umbrella, the functional equivalent of a crowbar, he requires the protection of his teammates in order to complete a map's objectives.

Sometimes referred to as "the prez," or more recently, "Mr. Potato Head," the Civilian has also been heavily used for fun/skill maps. These maps are usually an adventure made by custom mappers where players (usually working as a team) are given the basic objective of reaching the end of the map, with various challenges along the way. For unknown reasons, a new model has not been provided for the Civilian.

Game types
The multitude of ways entities can interact in Team Fortress and Team Fortress Classic allow for an almost limitless amount of different game modes. This is one of the reasons the mods were so successful. This is a list of some of the major game modes, complete with examples of popular maps.

Capture the Flag
Capture the flag (CTF) is a simple mode where players must get a flag from the enemies' base and return it to their own base to score. Several game modes based on CTF exist, including some variations where players instead have to take their flag to the enemies' base and modes with multiple flags.

Territorial control
Territorial control maps consist of several command points that a player can capture by either standing on it or bringing a flag there (depending on the map). A team scores points for each command point it controls at set intervals. Most maps include a bonus and "reset" for capturing all command points.

Attack and Defend
One team defends a base and another team tries to capture that base by bringing a flag to multiple capture points situated deep inside the base.

Hunted-style
One player is the VIP/Civilian class (usually blue team). He needs to traverse the map to get to an escape zone without being killed by the assassin team. The other (usually red) team act as bodyguards to the VIP, in charge of escorting him to the designated safe zone.

Shutdown CTF
Shutdown is a variation of capture the flag where the players must first complete an objective (such as disabling a laser by pressing a button) before gaining access to the flag. The flag-blocking objective typically resets at regular intervals. (For example, the laser reactivates.)

Skill maps
Skill maps or practice maps are for perfecting certain skills, such as conc jumping, rocketjumping, strafe-jumping, and climbing. These maps consist of increasingly hard jumps that players have to complete to reach the end of the map. Most maps have some kind of reward in the end.

Team Deathmatch maps
Often called DMs. Two to four teams (these maps often have yellow and green teams as well) fight for frags instead of flags. Whomever kills the most enemies wins. Most all regular Half-Life DM maps can be played as TFC DMs too. They can make for an enjoyable change of pace and also allow players to sharpen their combat skills without worrying about flags or other objectives.

Sniper War maps
Are a variation on Team Deathmatch but each team consists of Snipers only. Such maps often feature various sorts of barriers and obstacles, to prevent the teams from closing to use weapons besides their scoped rifles.

Sports War maps
These maps are based on popular sports. Flags are generally replaced by a ball. Push, for instance, is a soccer game where both teams try to grab the ball and bring it to the enemy's goal. In Murderball, four teams try to grab the ball and hold it for as long as possible. For each second a team member holds the ball, a point is scored for the entire team. If the ball holder is killed the ball instantly returns to mid-field. So it can become a bloody game of Hide and Seek or Hot Potato.

Competition
Since Team Fortress Classic is naturally a team game it is not surprising that it has long been a popular game in the electronic sports scene.

Team Fortress Classic teams (or clans) have many leagues available for them to take part in. As well as the major online leagues there are many leagues dedicated to TFC as listed below by region:

North America
 * STA (Stronger Than All)
 * TFL (Team Fortress League)
 * UGC (United Gaming Clans)

Europe
 * UKTFCL (United Kingdom Team Fortress Classic League)
 * WPTFCL (Wireplay Team Fortress Classic League)
 * NTFCL (Neoclassic Tactic & Fighting Challenge League)
 * VTFL/V-Ladder (Vitality Team Fortress League / Vitality Ladder)

Oceania These leagues can be found at ozfortress
 * ozfl (ozfortress league)
 * MLF (Major League Fortress)
 * SoO (State of Origin)
 * ADL (Attack, Defence League)
 * ozfortress cup (International tournament)
 * RvB (Red vs Blue community challenge)
 * NZFL - (NZFortress League found at NZFortress)

Asia


 * FPSJP TF (First Person Shooter Japan Team Fortress Classic League]

Over the past years there have been several international TFC tournaments, centered around Europe but also including team USA and team Canada under the name of the European Championships of Team Fortress Classic. This is one of the most prestigious TFC competitions, with only the best players playing for their country. The leagues are covered by live shoutcasts providing play by play commentary, often alongside visual broadcasts provided by HLTV, which can accommodate more than 200 spectators for the most popular games.

The most serious competitive clans once had the chance of playing for money in tournaments like those organized by the Cyberathlete Professional League. However, TFC has not had a presence at these large international events in recent years, and CPL prizes never became as large as those offered for the Counter-Strike tournaments or the $1,000,000 (USD) Painkiller world tour.

History
Before TFC there was Team Fortress, a 1996 QuakeWorld mod. TF's developers were working on Team Fortress 2 as a standalone game, but later joined Valve Software and ported the original as a mod for Half-Life called Team Fortress Classic in April of 1999. Despite the company's 1998 statement that Team Fortress 2: Brotherhood of Arms would be released "soon," the game remained in development of one form or another for eight years and has been on Wired magazine's top ten vaporware list every year since 2001. On July 15, 2006, Valve announced that Team Fortress 2 (Brotherhood of Arms was dropped from the title) would be released with Half-Life 2: Episode Two for the PC, Xbox 360, and PlayStation 2. The release date for Episode Two is currently Winter '06.

Since its release in 1999, Valve has introduced various changes into the game. Perhaps the most momentous was TFC 1.5 (released on June 8th, 2000), which, amongst other things, increased the Pyro's flame damage, reduced the HWGuy's AC damage, introduced new maps and map types such as Dustbowl, a new GUI menu interface and optimized the game's code for smoother, faster play. With this release, the game was officially named Team Fortress 1.5 to distinguish it from earlier versions. However, most players and fans still referred to it as TFC. Valve's last major revision to TFC 1.5 was released in October 2001. It was with this release that Valve began the long transition to its Steam system, which was finally completed in July 2004. Before this Valve released a Steam-Only version 1.6, which also introduced the Engineers' teleporters and a single new map (Ravelin, which was Valve's first new map release in nearly 3 years). Despite this, TFC 1.5 remains popular especially among veteran players, some of whom have found ways to port the teleporters and Ravelin over to 1.5.

For much of its early history, TFC was second only to Counter-Strike as the most played and popular of online games. For a long time afterwards it consistently ranked among the top 5 or top 10.

NeoTF
NeoTF is a server-side modification for Team Fortress Classic which first appeared in 2001. NeoTF adds many new elements to the game which can turn it into a completely different experience. Engineers, for instance, in addition to the usual Sentry Guns can also build Multi-Guns (MGs). A newly built MG is inert and must be upgraded by a non-Engineer teammate, who can accomplish this task simply by running up and touching it. The type of MG it upgrades to depends on which class touches it. If a Pyro upgrades it becomes a flamegun. If a Medic touches it; a plague gun (from which even enemy Medics are not immune). Soldiers can turn them into rocket launching guns, etc. Inert MGs may also be captured by the enemy if they manage to upgrade them first.

Other features of NeoTF (NTF) include: Spies can call airstrikes which can devastate outside areas. They can also fly on hoverboards and listen into the opposing teams' private chat. Soldiers can launch remote helicopters with deadly missiles, which they can pilot as well as build SAM launchers to shoot down enemy remotes. Snipers can build anti-rockets shields to protect themselves from Soldiers' and Pyros' long range weapons. Demomen can build mines. HWGuys can build mortars. Pyros have freeze rays and jetpacks. Scouts can build teleport disks or become invisible, for a short time, to enemy SGs. Medics can launch deadly, insect-like creatures called Snarks and build anti-grenade pods which can also heal teammates.

From this partial description of only some of NeoTF's features it can be seen how it can add to TFC's already very high replayability. Thus NTF has contributed to TFC's enduring popularity.

NTF adds new levels of complexity, especially for newbies. For instance, those unfamiliar with the game's console (an interface which allows commands to be executed via a command line prompt) or the concept of binding a command or function to a key using the console, will find themselves lost in an already complex game, since one must at least know how to bind a key to use any of the special features in NTF. It is, therefore, highly recommended that beginners familiarize themselves well with regular TFC before seriously attempting play on a NeoTF server.

Contemporary issues
TFC can no longer be played on the WON network (unless a player knows the IP of the server he or she wants to play on) as Valve Software has shut it down. In order to play TFC, users must now use the Steam platform. The advantages and disadvantages of WON (and its user-created replacement WON2) vs Steam remain controversial issues within the TFC and Half-Life communities.

Like Counter-Strike, there are a few bots (AI opponents and teammates) for online multiplayer and offline single play. Some of the most famous bots for TFC are:


 * 1) FoxBots
 * 2) OddBot &mdash; An early bot which is no longer supported.
 * 3) HPB Bot &mdash; The original bots for Half-Life