Tremulous is a team-based real-time strategy game that comes in a first-person shooter format. It is developed by the company Dark Legion Development and was first released in August of 2005. The basic idea of the game presents a rivalry between aliens and humans. The goal of the game is for either team to defend their respective bases while attacking and conquering the enemy’s base and killing the members. Members of a team must also work together to construct their home base as well as a structure called the Spawn, which reinforces the team in the event that some of its members are killed in battle. Members of the team of humans can choose from a wide selection of armor and weapons to defend their base, while members of the alien team evolve into stronger classes that have distinctive abilities.
In Tremulous, upgrades can be earned by reaching certain levels and purchasing game currency. Members of the human team acquire credits, while alien team members are awarded “frags” or “evos”. Apart from eliminating members of the opposing team, the goal of the game also includes preventing the enemy from respawning, which is accomplished by destroying the Spawn mechanism. Other important structures required by each team include healing machines and automated base defense.