Tremulous

The game features two opposing teams: humans and aliens. Each team must attack the enemy's base and team members, while defending their own base

Gameplay

Tremulous is a first-person shooter with elements of real time strategy. Each team must construct and defend a base, consisting of structures which aid the players in some way. The most important structure is the spawn, which provides each team with reinforcements to replace players who have been killed.During a match, most players engage in fighting the enemy, while others maintain the base and construct new structures. In order to destroy the enemy, humans utilize various weapons, armor and other upgrades, while aliens may evolve into more powerful classes, each of which possesses unique abilities.The teams do not have access to all possible upgrades and buildings at the beginning of the game. Each team must reach a threshold of frags in order to advance to the next developmental stage. The point at which a stage change occurs varies dynamically depending on the number of players on each team. Each new stage brings more upgrades for the humans and more classes for the aliens.

In addition to requiring a certain stage, each human item or alien class must be purchased using currency earned in game. The aliens are awarded evos for killing their foes which may be used to evolve. The Humans gain credits. Players earn currency by killing enemy players or by destroying key enemy structures; the amount of received currency depends on what class the opponent was (or what structure was destroyed) and how much of the target's total damage was dealt by the killing player. As a mechanism to encourage builders, who naturally don't engage in combat, players are also rewarded currency every two minutes by simply staying alive.

Builders are responsible for construction of new buildings and base maintenance. Each building takes up a certain number of build points available to each team. The number of build points can vary from map to map and server to server, limiting how large bases can become. To reduce the likelihood of the match ending in a tie, most games enter a sudden death mode ten to fifteen minutes before the draw/tie time limit. This is a period during which the building of most or all structures is prohibited, allowing attackers to more easily overwhelm the defender

Alien

The alien base is centered around a structure called the "Overmind", which is needed for their other structures to function and new structures to be built.

Aliens spawn from Eggs. Eggs work even when the Overmind is dead, but new eggs cannot be built without it.

As they earn evos, alien players can evolve into a new form in order to upgrade their health and gain new abilities. As the vast majority of alien attacks are melee attacks, most of these creatures depend on agility and special movement techniques such as wall-walk, wall-bounce, charging and pouncing over long distances to close the distance between themselves and their enemy.

Humans

Human base attacked by dragoons early in game

Humans utilize various weapons, armors and other high-tech equipment as a means to augment their combat abilities. They are primarily suited for ranged fighting and need a strong, defensible base in order to survive. They can save up to 2000 credits for purchasing upgrades at the armory, which range from 70 to 600 credits in price. At the core of the human base is the "Reactor", responsible for powering nearly all other base equipment. If it is deconstructed or destroyed, automated defenses and upgrade structures are rendered useless; if it not immediately replaced the human team is usually defeated.

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