Extinction

Extinction is a game mode featured in Call of Duty: Ghosts. The gamemode features up to four players fighting aliens in a post-apocalyptic world. Players will have objectives, many of which are to destroy alien hives with a drill and defend the devil by all means. Players will also earn money from either killing/shooting aliens, search hidden garbage/boxes or completing objectives. They then can use this money to buy ammo, weapons, and equipment such as the I.M.S. or Sentry Gun. There will also be traps that can be used against the aliens as shown in the trailer and the achievements, some of them are the electrical fences and fire pits. There are four classes for the player to choose from, Weapon Specialist, Tank, Engineer, and Medic. There are 30 levels, which unlock various weapons and upgrades. The mode is not infinite round based like Zombies but has an ending and is much more linear.

Trivia
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 * Extinction marks the first official and canonical appearance of aliens in the franchise.
 * The story takes place 2 weeks after the ODIN missile crashed into earth.
 * The time is simply shown as July 24 9:15:23.
 * The starting pistol can be chosen before starting.
 * The pistol can be upgraded to have a muzzle break, an extended clip, and finally duel-wielded.
 * $60 is awarded to the player if he/she kills the standard alien and $30 for an assisted kill.
 * $300 is awarded for killing a scorpion, and $200 is awarded for an assisted kill
 * This system, notably the money given for killing a standard alien, is very similar to zombies, where you will recieve 60 points for a standard kill.
 * Barrier hives are large alien hives that must be destroyed to continue throught the map. The helicopter from the beginning of the game returns to shoot at the barrier hives. It can take quite some time for the helicopter to destroy a barrier hive by itself.
 * Skill points spent in one game do not carry over to the next. Each classes skill set is reset at the start of every game.