Dr. Tercorien worked in a civilian hospital before he was drafted into the U.S. Army, serving just prior to the Great War. He doesn't recall the exact events that led up to his abduction and has no memory of the time between then and now because he was kept in cryogenic stasis the entire time. Elliott is good with technology and medicine. He's not so good with people, or bravery or sobriety. While he's capable of defending himself due to military training, he goes to great lengths to avoid getting in situations where defending himself might be necessary.
Among the Stars: The Lone Wanderer has the option of bringing Elliott Tercorien with them as a companion to the cryo lab to help out. Elliott can either put the other two surviving members of his squad out of their misery or revive them. If they are revived, they only have a limited amount of time before they die.
This Galaxy Ain't Big Enough...: If Elliott survived his section in Among the Stars, he will help in the last battle by keeping aliens off the Lone Wanderer while they fight the other mothership.
If the Lone Wanderer has any alien biogel, Elliott has the ability to modify the regular biogel into adapted biogel. The adapted biogel has a much higher healing capability but still contains the either helpful or nasty side effects of regular alien biogel.
After being taken to the cryo lab, he will gain the ability to make cryo grenades and cryo mines. The first batch consists of 3 of each and can be taken after 1 hour. The player character can then receive another 2 cryo grenades and 2 cryo mines every 3 hours. All conversation options which allow the player character to request cryo mines and cryo grenades are only available while Elliott is in the engineering core section of Mothership Zeta.
It is still possible to get cryo mines and grenades after the space walk, by going through the teleporter after the compression sequence and asking him to make some while in the engineering core.
After the This Galaxy Ain't Big Enough... quest is completed, the Lone Wanderer can return to the mothership at any time and ask for weapons. If Elliott has some stockpiled, he will provide what he has in his cache. He gives either alien atomizers, alien disintegrators or shock batons, and it is common that he will give multiple weapons at once. After receiving these weapons, the player character will have to wait or return in another few hours for him to salvage more.
Unlike normal non-player characters, Elliott uses up ammunition in his inventory, similar to a permanent companion. Therefore he is likely to eventually run out of ammunition for his assault rifle, and be forced to either scavenge weapons from the environment or resort to his fists. All other Mothership Zeta allies have infinite ammunition. However, ammo respawns on his body for his assault rifle during key parts of the campaign to take the mothership over.
Elliott is the only non-player character in Mothership Zeta who picks up and uses weapons from the environment, excluding Somah, who may pick up a weapon at the beginning of the add-on if it has been knocked out of an enemy's hand. All other non-player characters stick with their default weapon.
Elliott does not have any tagged combat skills, and therefore has terrible aim with any weapon he uses, including his default assault rifle.
In the engineering core, he may ask Somah what has happened since he was abducted. When she explains the Great War and its ramifications, he responds with a remark of fear and horror; she responds to him by saying, "Sorry, you'll just have to learn to deal with it like the rest of us."
The dialogue option to have him accompany the player character to the cryo-lab is only valid once, as opposed to the two other possible companions. If player character asks him to stay in the engineering core after already having visited the cryo-lab with him, he will decline to rejoin them on grounds of the player character already having done some good there. This might preempt him from gathering the cryo-equipment he uses to fabricate cryo-mines and grenades. While he is still the player character's companion, they can travel to and fro the cryo-lab at liberty without losing him.
If the Lone Wanderer had already finished another add-on, Operation: Anchorage (add-on), they will make a remark about Elliott Tercorien's armor.
"Yeah, I was considering that too. We can't let the aliens experiment on them any more. It just isn't right. But maybe we should give them a chance to fight with us. It's better to die that way than to live through years of agony."
"Isn't it obvious? They're probably using us as guinea pigs, examining our anatomy. Once they've figured out how to make exact copies of us, they'll send those copies back down to earth to take our places. When they've copied enough of us, they'll turn on us and take over the world. Come on, how can you not see that coming?"
If asked what the aliens want with Earth he will make up four different explanations for alien encounters from various sci-fi movies, from Independence Day for the resource consuming theory, from Star Trek for his idea that the aliens seeded life on Earth, from Invasion of the Body Snatchers for his idea of them wanting to replace people on earth with clones and one theory of earth having inadvertently broadcast radio signals amounting to a declaration of war on them which is a possible reference to Mars Attacks.
pcps3xbox360 Elliott may suddenly stop making cryo grenades and mines. The dialogue option will still be present, but choosing it will result in Elliott saying "not yet, still working on them" even though time has passed.[verified]
The bug's cause hasn't been identified, and only a small number of potential fixes are known.
Loading a save that was made before the bug occurred should fix the bug.
Uninstalling and reinstalling the add-on may fix the bug, but may also cause numerous other bugs.
Sometimes, waiting in one-hour increments may cause Tercorien to start creating more cryo weapons.
Waiting for a short time and letting Tercorien walk around a bit may also prompt him to build more cryo weapons.
pcxbox360 Elliott might disappear all together after finishing This Galaxy Ain't Big Enough.[verified]
pcps3 Sometimes if you make Elliott an enemy and then travel back to the Capital Wasteland, he will travel back to the Capital Wasteland with you and stand next to the beacon acting like he is still in space.[verified]
pcxbox360 Elliot's hands may enlarge when equipping alien weapons.[verified]
xbox360 Elliot's forehead may lose its texture, although it is only cosmetic.[verified]