Scene summaries may contain spoilers
Petra gloats about this new world, and how she had turned off the technology that suspended consciousness for the sleepers. The creatures here will find new homes inside your skins. Maxie threatens to destroy her, but Petra reminds her that she can kill all your tribe. They're done for anyway, but she knows you'll try to save them. Ellie speaks to you secretly again. She's the last of her tribe, but she can save your people with her transporter, two-by-two. Then you can use her bracelet to save yourself and one other. Petra demands that you carry her out towards the monolith on this new world to get her reward.
The Sleeping Towers have landed, and the sleepers will be drawn towards the monolith. Petra says you've been orbiting the planet for 120 years, ever since the flood she caused destroyed a circuit. She was trapped until you finally freed her. Up above you see many other ships like yours, woken by your use of the Rings, and all brought here to spring the trap.
The monolith opens as you approach. Music that calms the sleepers is coming from somewhere. A rift opens in the monolith and you enter. There are pale, writhing things waiting for you. You hear screams and see the pale things begin to take over the bodies of the sleepers. They're watching you. Petra says they will have you after she gets her reward. Keep moving!
You've lost them for now. Ellie says that after one more transporting trip your tribe will be safely away. Petra says the centre of the monolith is an advanced ship. It left Earth after yours but arrived before you. Descendants of its passengers have been here long enough to become altered. Inside the centre are small chambers like the ones in the towers. Petra instructs you to put her into one. The lid closes and she screams as it begins to work, restoring her youth. Ellie speaks to all of you, saying that your tribe is safely away from Petra. You use a spear to trap Petra in the chamber. If this is a ship, maybe you can fly back to your people.
On the bridge, you see the towers from many ships landing. Maxie points out that the music controlling people is coming from this ship, so maybe if you fly it away, the other people will follow. You use the Rings to power up the ship, but Sam spots that Petra is breaking out of the chamber, younger and much, much bigger. Ellie says she can reprogram the teleport to send her into space, but one of you will need to take her there, and there won't be any coming back. Your friends debate who should go, but you've already made the choice. Run!
Sam speaks to you through comms. Petra is heading towards you and she's dangerous. You'll need to hold on tight. You grab her and Ellie starts the teleport. She sends you into deep space where Petra will live forever, eternally alone. Maxie says that the chamber should heal Paula. Sam tells you that the towers are heading back to their ships, and they should follow them. It makes Sam the captain. They'll find a real paradise. Ellie tells you to let go of Petra, and thank you for saving them all.
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