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The Temple Ship

Temple Ship Assault is the final mission in XCOM: Enemy Unknown. This mission takes place aboard the Temple Ship off the coast of South America and has the official designation of Operation Avenger.


The mission becomes available after building the Gollop Chamber and having successfully activated the Ethereal Device with The Volunteer.

Make sure that you are 100% prepared when you start the Temple Ship Assault

Activating the Gollop Chamber is a turning point, after which progression in the game is virtually stopped; no time-demanding actions can be performed and no other missions can be undertaken.

Mission Brief[]

We finally have the strength to face the Ethereals on their own ship. The future of humanity is at stake. Expect extreme resistance.

Mission Objectives[]

When the Volunteer dies, you must restart. Don't let this happen to you.
  • Force entry to the Temple Ship's bridge
  • The Volunteer must survive

If the Volunteer dies you lose the mission and the game but you will be given a chance to restart the mission (even on Ironman).

Mission Site[]

The Temple Ship layout is predetermined, and consists mostly of pathways with guardrails that serve as cover. The layout is also very linear, all paths parallel, leading in the same direction. Nearly every area in the ship features multi-elevation environments, which can benefit the player if soldiers are always positioned at a higher vantage point than the enemy. For a substantial part of the mission, there is a central pathway available that is positioned higher than either of the side pathways.

In areas that don't have a central, highly elevated pathway, full cover is available, making it easier to perform frontal assaults with close-combat units, such as shotgun-equipped Assault Class soldiers.

Enemy Types[]

Unlike most missions in the game, the Temple Ship Assault features predetermined groups of enemies whose positions are fixed, becoming discovered or spawning as the player's squad progresses through the ship. During the assault, the player will encounter every alien type existing in the game, except the Outsider (and the new types introduced in Enemy Within), and the Uber Ethereal will comment on each alien race and the player's progress.

Area by area enemy types[]


This is the final fight, it is long and all the hardest enemies are going to be thrown at your squad. You're going to want to take all your best soldiers, preferably all Colonel rank. You're going to want everyone toting the very best equipment: Plasma weapons, Alloy Cannons, Titan Armor and Ghost Armor. Archangel Armor is less useful as the mission requires constant advancement and the map's various bulkheads and doorways restrict extreme range shots and general flight movement. That said, a Squadsight Sniper is extremely advantageous to bring along as most rooms offer decent perches from which to pick off enemies. A Heavy with HEAT Ammo and packing a Blaster Launcher will be able to deal some serious damage at a couple critical sections. An Assault with Rapid Fire and Lightning Reflexes or Ghost Armor can be useful for scouting or dislodging entrenched enemies. At least one Field Medic Support with Savior and Improved Medikits (for the option to heal 10 HP) will likely be crucial for survival and mission success. Absolutely essential to mission success is the survival of the Volunteer who will be wearing Psi Armor so equipping a Mind Shield (maximize Psionic potential and resistance) and/or Chitin Plating (to make up for the lack of heavier armor) tend to be good options.

As this is the final mission, you can leave the Arc Thrower at the base unless you plan on taking any S.H.I.V.s, provided you have completed the Foundry project S.H.I.V. Repair. One Foundry upgrade that is really ideal to have completed before going on this lengthy the mission is Ammo Conservation.

During the assault, most enemy groups appear in fixed locations after the squad crosses specific points. When the enemy is engaged, it's preferable to have every soldier in a tactically sound position and with action points available. Due to this, it's best to move carefully with regards to possible positioning if the enemy is engaged. However, considering that most enemy troops are not mobile before discovered, if the point man (the first advancing soldier) doesn't alert any aliens, others can usually be positioned behind him / her without regards to cover. Using Overwatch is advisable at the end of your turn since warping in aliens will be met with plasma fire.

Area by area guide[]

There are no enemies in your starting area (the landing bay) and there are three doorways into the rest of the ship. By orienting your camera with the doorways at the top of your screen, you create the camera angle that will be considered "up" or "forward" for the purpose of further directions. The center, right, and left positions of the door create a symmetrical configuration that follows through most of the ship.

1st Area[]

Advancing through the first set of doors, you will encounter a Sectoid Commander and two Sectoids on the main landing plus another two Sectoids on the path under the right archway. The Sectoids should be minimal threat at this point in the game but taking down the Sectoid Commander should be a priority to avoid any Mind Control shenanigans. One round after engaging the Sectoids, the Cyberdiscs and Drones will appear on top of the archways; the Cyberdisc on the left will have two Drones and the right one will only have one Drone. Snipers with Double Tap or Heavies with HEAT Ammo can make short work of the Cyberdiscs, allowing the other soldiers to finish off any Drones that survive the Cyberdiscs' explosions. Also the Volunteer can use Rift to easily annihilate either group of robotic enemies.

It can be difficult to avoid taking damage in this area as there is little full cover and the Drones advance ahead of the Cyberdiscs absorbing your overwatch fire. If you can kill the Sectoid Commander before the Cyberdiscs advance consider hunkering down under a smoke grenade and/or Telekinetic Field. There are some line-of-sight quirks in this room so letting the Cyberdiscs get closer can make returning fire easier. If you do hunker down, spread out as much as possible to avoid becoming a tempting grenade target.

2nd Area[]

The squad can enter this large square area by either taking the central ramp or either the left or right doors from the previous area. The ramp leads to a high raised walkway with two parallel lower walkways that cross through the center the room; the doors lead to lower pathways that grant access to a high balcony on either side of the room. There are is a single Floater on the both the left pathway and right pathway, a Heavy Floater on the right balcony, and two Floaters near the exit at the end of the central walkway. While there is abundant half cover in the area, your soldiers (especially any using the high central walkway) can open themselves to severe flanking if they over extend into the area and activate all the Floaters at once. After one round, 3 Chryssalids will teleport in close to the area entrances, one on the left pathway and two on the right pathway. Fortunately, you have a whole turn before they activate so they shouldn't prove too troublesome.

A well placed Sniper on the high raised walkway should be able to pick off any enemy in the room. The Chryssalids can be blocked from reaching the raised walkways by placing soldiers on the alien transport devices. Once all the enemies have been killed, the doors to the next area should open; note that if this doesn't happen double check this and the previous area for any missed enemies. If your search turns up empty, the action has likely become bugged which will prevent any further progress and it will be necessary to restart the mission.

It is generally best to keep to the high ground in this area to gain the aim and defense bonuses, and to ensure that every enemy can be engaged as soon as they spawn.

3rd Area[]

This area consists of three separate walkways that follow on from the previous room: the center walkway is elevated while the left and right pathways are lower and each has an extra door in the middle. The center path contains two large pieces of cover and two Thin Men on the left side of the pathway. A third Thin Man will be located one of the lower pathways; it will appear on whichever side that a soldier first is able to see past the middle door. As the Thin Men have tend to retreat to full cover when spotted, sometimes even into the next area, so it can be advantageous to use soldiers with Ghost Armor to get the drop on them. Given the narrow confines of the walkways, be aware that the Thin Men's poison gas clouds can create choke points for non-immune soldiers.

4th Area[]

Following on from the previous area, this area's central entrance opens onto a high balcony which over looks the small open areas beyond the lower left and right entrances. There are stairs up from the open areas and stairs down from the balcony that all lead to broad middle elevation. On each side of the middle elevation (overlooking the stairs up from the lower entrances) is guarded a pair of Mutons. A lone Berserker also patrols the middle elevation somewhere between the two groups, just down from the high balcony. The limited cover between the entrances and the Mutons' positions can prove problematic because it forces your soldiers to either bunch up (making them vulnerable to the aliens' grenades) or to engage in an uneven shoot out. Here is another place where soldiers with Ghost Armor can help neutralize the aliens; Mind Controlling some of the Mutons can also help even the odds and can prove highly useful in the the next area.

Patient players can simply use Rift to make short work of the Mutons. Hugging the rear wall to avoid triggering the Berserker, the Volunteer can take out a pair of Mutons with a single use of Rift, wait a few turns, move to the other side and repeat. Then, with your squad in position, the Berserker by itself is hardly a threat.

5th Area[]

The middle elevation of the previous area extends forward becoming a wide balcony that overlooks the next area. Stairs lead down from the left and right sides of middle elevation to two long pathways which flank an even lower, open courtyard-like area containing two Sectopods located close together near the middle. The balcony and the side pathways all offer excellent vantage points for firing down on the Sectopods, but sure to maneuver all your soldiers into position before catching their attention; allowing both Sectopods to tag team one of your soldiers will end in a quick death. Also remember that the Sectopods' Cannon Fire has an area of effect will quickly disintegrate cover and grouped up soldiers alike. If you happen to have a Mind Controlled Muton still in play, you can use this unit to scout forward to spot the machines and then make a suicide run on them; managing to get the Muton between both Sectopods will heavily damage all three when the Sectopods fire their Chest Cannons. Snipers with Squadsight and Archangel Armor should be able to fly high at the back of the wide balcony and shoot freely at the Sectopods without being seen themselves. Given the Sectopods close starting proximity to each other leaves them open to heavy damage from a well placed Blaster Launcher shot (especially if the Heavy has HEAT Ammo); along the the same idea, a well placed Rift should encompass both Sectopods and can easily kill them both over its two turn duration. When both Sectopods are destroyed, two Muton Elites will spawn at the far end of the room, where stairs up from the courtyard and pathways all converge into the same elevation. This spawn point grants the Elites both high-ground and cover allowing them to wait to ambush you, but they may instead move forward, firing or tossing grenades at the first soldier they see. Units with Ghost Armor or a Sniper with Squadsight can be crucial to safely dislodging these aliens if they decide to entrench themselves on the high ground.

Final Area (the bridge)[]

The cathedral-like bridge of the Temple Ship.

The Uber Ethereal encountered on the bridge.

Beyond the single door leading into this final area is a long thin hallway which opens to a mid-elevation platform of large symmetrical room; a set of stairs leads down from this platform to a lower center area which has two sets of stairs leading up to another mid-elevation platform at the back of the room. Ramps up on both sides of the platform lead up to E-shaped balconies that face each other on either side of the room. At the far end of the room the Uber Ethereal awaits on a high, thin balcony sitting above the rear platform; behind the Uber Ethereal sits a second Ethereal Device.

Once a soldier moves within sight of the Uber Ethereal, (approximately upon reaching the half cover at the edge of the entrance platform) a short cinematic triggers where the Uber Ethereal will speak of the Ethereals' existence, and why they have attacked Earth; after the cinematic finishes two Ethereals spawn on the balconies' E-tines closest to the Uber Ethereal and two Elite Mutons spawn on the rear platform, one to each side of the Uber Ethereal's balcony. The Muton Elites tend to charge forwards to attack or grenade your squad while the Ethereals focus on Mind Controlling any susceptible soldiers. Fending off those Mind Control attempts is critical to keeping the fight from snowballing out of control, so outfitting your team with Mind Shields (especially the Volunteer) can be advantageous or using Psi Inspiration and Combat Drugged Smoke Grenades may give your soldiers the temporary Will boost required to finish the fight.

The long hallway into the room creates a dangerous bottleneck for your soldiers, so it's critical that you carefully move all your soldiers into the room before spotting the Uber Ethereal. A good basic strategy to win the fight quickly is ignoring all the lesser aliens and focusing all your fire power on killing the Uber Ethereal, as its death results in an immediate victory. That said, the Uber Ethereal's high deflection rate can make pulling off a one turn kill difficult and can leave your squad open to a harsh retaliation from all the aliens present.

If you have at least two maxed out Psionic soldiers, another good strategy is to form up your squad near the entrance, spawn the aliens, Mind Control both Muton Elites and spend any remaining actions damaging the Uber Ethereal; in this case, the Ethereals will then almost certainly spend a turn killing the Elites instead of attacking or Mind Controlling your soldiers. This leaves you with second a full turn of actions from your squad do enough damage to kill the Uber Ethereal and win. A variation of this plan, if your Psionic soldiers are strong enough, is to Mind Control both of the other Ethereals instead. If you successfully pull this off you're pretty much a guaranteed win as the next turn you can then use the Ethereals to Mind Control the Muton Elites or just drop a barrage of Rifts to annihilate the Uber Ethereal!

Another strategy is to leave your Squadsight Sniper safely in the previous area, set up in the middle of the 3 tile long block of cover just outside the bridge door. Simply send in someone with Ghost Armor to spot, and pop away at the Uber Ethereal with impunity. If your Squadsight Sniper also has Ghost Armor and Double Tap you can potentially ending the fight in one round by cloaking for the first shot (automatic critical hit) then following up with Headshot to hopefully kill the Uber Ethereal with a second critical hit.

Heavies with blaster launchers can be set up before triggering the fight such that they are just within range. Since the blaster launchers cannot be reflected they are a good way of causing guaranteed damage. Two blaster launchers are enough to severely wound the Uber Ethereal and outright kill the Muton Elites flanking it. Rift can also cause guaranteed damage, though with reduced effectiveness. After that, it should only take one or two shots from your remaining soldiers to kill the Uber Ethereal without it having a chance to move or attack.

If playing XCOM: Enemy Within, an alternative for a "kill in one" is using a MEC with the Proximity Mine Launcher Tactical Subsystem. Just move your squad inside the bridge but without triggering the cutscene, and lay your MEC mines in the place where the Uber Ethereal will appear (as you can lay one mine per turn per MEC and each MEC has up to 5 mines, this can take as many as 5 turns to setup). Once the mines are laid, just advance one of your soldiers so it triggers the Uber Ethereal; the mines will be triggered causing massive damage to it (up to leaving only 1 hit point, playing with Damage Roulette option). Then just finish the Uber Ethereal with any of your soldiers.

Players not confident in a one-turn kill may consider sending any soldiers with Ghost Armor out ahead while cloaked. This has the dual advantage of getting better shots next turn while limiting the damage from enemy Rifts - these can easily set off a chain reaction of panic and reduce the fight to chaos.


The squad feels the Temple Ship shudder.

With the Uber Ethereal's death, the Temple Ship begins to shudder and The Volunteer receives a vision of the Temple Ship's destruction creating a miniature black hole which swallows the Earth. Acting quickly, the Volunteer orders the rest of the squad to go and then seals the bridge. Activating the Ethereal Device on the bridge, the Volunteer is able to engage the Temple Ships engines. The Skyranger is seen escaping as the ship begins to move. The Volunteer destroys the Temple Ship after it exits the atmosphere and disappears from the bridge in a violet flash; the Volunteer's apparent sacrifice saves the planet and ends the aliens' invasion.


Temple Ship Assault is the final mission of the game, and no continuation is possible. As such, the mission doesn't offer any rewards.


  • Mind Controlling a Floater in the second area and then Launching it into the final bridge area will cause the game to act as though all of your units have entered the final room, preventing critical doors from being opened. This is because the player is expected to advance through each chamber in turn, with the Uber Ethereal delivering plot exposition as the XCOM squad proceeds through the chambers. The game is thus programmed to open doors after certain enemies are defeated, and by bypassing them it basically locks the rest of the troops out, thus forcing you to either kill the boss with the Floaters (unlikely), restart, or kill your soldiers if in Ironman mode.
  • If the Volunteer is being Mind Controlled by a regular Ethereal when the Uber Ethereal is killed, the game will act as if the Volunteer was killed and will result in mission failure. This can be avoided by killing the Ethereal who is Mind Controlling the Volunteer before killing the Uber Ethereal. Note, if it is the Uber Ethereal who is Mind Controlling the Volunteer, killing the Uber Ethereal will end the game as normal.
  • If the Muton elites are both dead/mind controlled, the 3 ethereals (including the Uber) are all severely damaged (less than 5), and out of range to mind control your soldiers then a bug in the enemy AI causes them to drain health from one another. This can result in an apparent 'revolt' among the Ethereals, even having them kill the Uber Ethereal and end the game through Psi Drain without you ever firing a shot.
  • Enemy Within: In the 5th area, sometimes the Muton Elites do not appear after the Sectopods are killed. This makes it impossible to enter the final area and finish the game. Restarting the game and/or reloading to a point before the Sectopods does not solve the problem.
    • This may be because the player missed a hiding enemy in a previous group, for example a Muton.
  • Steam-Version, Sept. 2013: It is possible to get stuck in this mission with a corrupt savegame if you save the game after you get one person just one step through the door to the last room and all other soldiers standing behind. This will result in a savegame in which all soldiers outside can not enter the last room anymore. The door is visually open but not passable thus rendering solving the mission almost impossible.
  • If one of the other enemies in the final fight is mind-controlled when the Uber Ethereal is killed, the mission will not end until the mind control expires or the mind-controlled alien is killed.
  • Enemies entering a previously used Rift seems to crash the game on some systems.
  • Units with Archangel armor can glitch into the nearest wall if they fly into the final room.


  • The name of this mission (Operation Avenger) could be a reference to the Avenger, the craft required to reach the Final Mission on Mars in the original UFO: Enemy Unknown. The same name is used for a prototype spacecraft developed by XCOM in The Bureau: XCOM Declassified as well as XCOM's mobile headquarters in XCOM 2.
  • Jake Solomon has clarified (via Twitter) that Volunteer does not die at the end of the game. In follow up Tweets, he stated that the final cinematic didn't quite get the story across that the Volunteer actually disappears before the Temple Ship explodes.
  • Though rare, it is possible to kill Uber Ethereal in the same turn you encounter him. Reportedly, by using a sniper with headshot, then firing rift at him with The Volunteer and finally finishing with any other soldier, should be enough to kill it. A single sniper with doubletap should also be enough to kill it.