Terror Site

Terror Site is one of the mission types in XCOM: Enemy Unknown.

Mission Brief

“

Alien terror attack in progress. Strong civilian presence, take care to avoid civilian casualties. Failure will have severe political consequences for XCOM.

”

Mission Objectives

Approach civilians to enable evacuation
Minimize civilian casualties
Neutralize all hostile targets

Acquisition

This mission type first appears during the second month and becomes active as part of the "random event pool" for each month of the game after that. Each Terror Site has its own difficulty rating which indicate the number of aliens packs present on the mission, with Easy usually having 2 packs and Very Difficult around 4.

Mission Site

Terror Site missions always take place in densely populated urban areas. The layout is chosen randomly from a set of hand-crafted maps. The pool of mission layouts for many locations of the world is shared. Terror Site missions also partially shares its pool of maps with the Alien Abductions mission type.

Urban areas typically consist of tight spaces with a lot of cover and multiple obstructions. This makes them good for mobility and flanking. Some maps also have multi-level buildings. Having Soldiers equipped with grappling hooks via Skeleton Suit or Ghost Armor can be very helpful.

Enemy Types

Depending on the stage of the alien invasion, these missions can feature almost any enemy type, with the exception of Ethereals and Outsiders; however, they typically feature some of the most dangerous enemies in the game, including Cyberdiscs, Sectopods, and an abundance of Chryssalids. Due to civilian presence, these are also the only missions in which the player will encounter Zombies in abundance.

Tactics

At the start of the mission, there are 18 civilians spread across the map, whose survival influences the mission results; a rescued civilian count at 14 or above is considered "Excellent." It is possible to rescue civilians by moving a soldier close to them; they will be shown fleeing the map which makes them immune to further attack. All the civilians do not have to be personally rescued, as any civilians still alive when all aliens are dead automatically count as rescued. However all civilians will count as dead if you lose or abort the mission, even ones that you've rescued. Explosives should be used with care, as they will kill any civilian caught in the blast.

Every turn, alien forces actively roam the area, killing every civilian they can find. When encountered, they will prioritize easily targeted civilians over distantly located XCOM soldiers in cover. As the mission is considered a success as long as at least 1 civilian is saved, it is advisable to prioritize squad survival over civilian survival.

Many Terror Site missions feature Chryssalids, which comes with an additional challenge. Civilians killed with by a Chryssalid's melee attack turn into extremely tough Zombies after one turn. To avoid being overrun, it's preferable to make Chryssalids priority targets when encountered on these missions.

Rewards

Aside from alien corpses, Weapon Fragments, and captured aliens, Terror Site missions confer pre-announced rewards from the affected country. Additionally, panic is decreased by up to three points in the country where the mission took place (varies depending on the number of civilians saved) and by up to two points across the continent (depending on the scoring in all mission areas); scoring Excellent in all three areas can be a way to provide a significant panic reduction to a troubled continent.

Failure of the mission results in immediate withdrawal of the affected country from the Council and a panic increase of the neighboring countries; these missions should not be failed or ignored if at all possible.