Scene summaries may contain spoilers
Peter asks Sam why he blew up the runabout. Sam says that there are escape pods, which he was going to tell you about after Jody was destroyed. He says he's looked her up and she carried out the New London bombings. Jody denies it, and says that there are only so many synth models. But first you have to make it to the salvation pods before the arachnomorphs find you!
You're getting close. You just have to hope there are salvation pods left. Jody says that she can stay behind to detonate the Azedrium, which should destroy the asteroid and prevent anyone else encountering the spores, but you have to tell people that it was a synth who saved you and Peter. Peter says it's a good plan, but with one change; he will be staying behind. He found a tiny tear in his suit and he's infected. He'd rather go out in a blaze of glory than have his head exploded by a spider. Run to the salvation pods, and he'll set up the charges.
Not far from the escape pods, but something sheared through the roof and it's coming down! Sam says that he's brought the Artemus' weapons systems online. He won't let Jody off the asteroid, even if it means Five dying too. Sam says that his mum and sister went back to help after the first bombing, and were caught by the second bomb. He heard his sister die. The roof is coming down so you'll need to run.
The laser fire is making the arachnomorphs go crazy. You'll have to take a side tunnel. You find a huge chamber full of dormant arachnomorphs, including one that is vast and fills up most of the carvern. It was asleep, but it starts to move. Quick, run to the tunnel on the other side of the cavern!
The huge arachnomorph is tearing up the tunnels. Peter encourages you along. He won't blow the asteroid up until you're safely away! The arachnomorph gets stuck, but it won't be stopped for long. You reach the salvation pod bay, but there aren't any pods left, just the shuttle from the Artemus. Sam has come to make sure Jody pays for her crimes. Peter and Jody plead with Sam to lay this to rest or the war will never end. The arachnomorph is getting free. Quick, follow Jody to the bulkhead. Jody warns Sam about it, but he doesn't believe her, and is eaten by the monster. Jody opens the bulkhead doors and you cling to them as the spiders are vented into space. Finally the doors close. You need to make it to Sam's shuttle before any of the arachnomorphs reach you.
The shuttle is intact and you climb on board just as arachnomorphs scuttle into the bay. Jody gets you out into space. Peter checks that you're out and says his goodbye. Make him sound heroic when you tell the story. As you leave, the asteroid explodes along with the Hephaestus and the Artemus. There's a cryostasis pod on board the shuttle. Jody will stay away for the journey home. As you settle in, Jody wonders about the synth who looked like her. Just one of those spores in Jody's lungs would be enough to wipe out the human race. Would it be right to do it, to keep her people safe? Good job Jody isn't her, right?