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Humans comprise the majority of both the Galactic Federation and the Rebel Fleet. Humans learn skills faster due to their reduced XP ability, have no notable weaknesses and are the cheapest race to hire from Stores.
- Skills improve slightly faster (10%)
Engi originate from the Engi Homeworld. They take 50 to hire, with the following special traits:
- Repair speed is doubled
- Combat damage is halved
The Mantis originate from the Mantis Homeworld. It takes 45 to hire them.
- Inflict 1.5x damage in combat
- 1.2x move speed
- Halved repair speed
Rockmen are strong creatures and take 65 to hire. Their abilites are:
- Immune to fire
- Movement speed is halved
- Health is increased to 150%
Zoltan usually appear in Engi Homeworlds or Engi-Controlled Worlds. They appear rarely, and it takes 65 to hire them. Their special abilities are:
- Provides (1) power to occupied system
- Health is 70
- Explode when killed, damaging all enemy crew in the room
Slugs are one of the rarest crew to find. Their advantage is the ability to see your enemy's crew, and to be able to see the rooms surrounding the slug in your ship if your sensor goes down. They cost 45 to hire.
- Telepathic powers reveal rooms and lifeforms even when sensors are down.
The Lanius are scavengers – metallic lifeforms that rely on the absorption of minerals to sustain themselves. They are available only in advanced edition and even then are almost exclusively found in the Abandoned Sector where they cost 50 to hire. They need no oxygen and also drain oxygen from the room they are in.
- Drains oxygen from rooms
- -20% movement speed
- No damage from suffocation
And a final 'secret' race:
Crystals can be found in Life support pods that are revived by scientists. Doing so also begins a special quest to the Rock Homeworlds.
- Lockdown power: When finished charging, sends crystals to surround the room they are in, making it completly invincible to damage (Only that specific room). Nothing can exit/enter the specific room until the ability wears off.
- Reduced suffocation damage
- Movement speed -20%
- Health 125
Killing the crew in first phase means they won't be there in the next two, same if you kill them in second phase: they won't be there in the final, so killing them can be a good tactic as they may trouble you later.
If you kill them all you won't win that phase or overall, instead the ship will go into auto-pilot and will slowly repair all its systems much like the auto-assault scout drones in earlier sectors. It's best to leave one enemy crew alive, maybe the isolated guy on their laser tri-shot; because fighting an AI Boss is much harder than fighting a single panicky engineer.
When the ship flees to its next phase your boarding crew will be killed if they are still on board, same if you destroy it completely with your crew on board, meaning their noble sacrifice won't go down in the credits.
Best Answer
Yes, crewmembers can be killed at any point, including in those types of encounters. There is no mercy for being the last crewmember, their life is just as much at risk as any others.
Generally I tend to avoid those enounters when a blue option isn't present, as the loss of a crewmember can be a pretty big setback in general, not just on your last crewmember.
Source: Personal Experience