This scene happens right after 'a_gate_forever_closed'.
I'm unhappy with a lot of the dialogue, it needs to be reworked.
Muts is running through the forest as fast as he can.
Wrex (chasing after, calling off in the distance): Wait Muts, it's not safe!
But Muts ignores him, he runs back into the clearing where the others are still picking berries, he makes quick eye contact with Frux before running again, sprinting back to the warren. Frux follows after him and soon the others are going back as well to see what's wrong.
Vox and the others watch, and then Vox turns to make eye contact with Wrex as he bursts out of the treeline panting. Vox can read what happened on Wrex's face.
Vox (preparing to go after them): Shit.
We see Muts reach the clearing surrounding Antioch. He's horrified by what he sees. All that's left are tracks and blood and bits of fur. The foxes have been here, they killed all the proles.
Muts runs into the warren as Wrex and some of the others come into the clearing as well. Wrex is still yelling after Muts but he freezes with a different sort of horror. The Deadwood has moved again. Before it was just barely into the clearing, but now the black trees are partially consuming the warren's superstructure. The library tower has been completely with black foliage. The Deadwood had moved forward by the length of a football field while they weren't looking.
More of the group cross the tree-line and into the clearing, we see Frux's reaction as she steps out into the aftermath of the carnage.
Synx (speaking to Frux): Frux...I think--
Frux (cutting her off sharply): Shut up.
Frux's eyes narrow as she sees movement coming out of the structure and is relieved to find Muts stumbling out. It is clear there was no one left inside.
The group, including all the cubs, are gathered around watching now, the cubs murmuring nervously, some terrified. As Muts wanders out aimlessly he spots Wrex away from the group, his head down in shame, he barely glances Muts.
Muts (approaching, furious): You did this!
Muts (cont'd, looking at the others as he shouts): He's the one who planned it! He's in league with the foxes!
Wrex refuses to look up, he seems like he's on the verge of tears.
Synx (interrupting from behind): He didn't do it. I did.
Muts and the others turn to see Synx with her head up defiantly, as if she's the one being accused. She raises her voice as she addresses the warren like the did before.
Synx: I'm the one. The one who killed them all.
Synx (cont'd, glaring at Muts): And I would do it again. It was necessary to ensure the survival this warren. The last rabbit warren.
Muts (furious): You're a traitor! You were supposed to protect us!
Synx (defensive): That's what I did! I protected the rabbits!
Synx (cont'd, addressing the whole group again) We all knew what the proles were! Feral and ferocious, consuming our resources while giving nothing in return. They didn't know our language or culture, many of them couldn't even speak anymore--these were not our people!
Synx lingers on this last point, as if she's trying to convince herself as well.
Synx (calmer): Now that the population has been stabilized crop production is self-sufficient. We can live in the warren as long as we want. Look there!
Synx points to the black trees partially surrounding Antioch's structure.
Synx (cont'd): One day the whole world will be like that. Enjoy your time on the surface because this the last time our generation will see it. And while the foxes and the wolves and the bears are consumed, we will survive. When the Deadwood recedes we will emerge to reclaim the surface that is rightfully ours!
Muts (scoffing, a twisted mix of laughing and crying): Survive?! We're nearly all dead already! You think you'll outlast them but you're no better than them! You're no better than the wolves!
There's a silence as Wrex and Synx exchange an awkward glance. Some rabbits in the council shift uncomfortably. Muts walks up to Frux.
Muts (whispering excitedly with a smile, almost manically, like he's starting to crack): Come on, let's leave. Right now, together. We'll go through the Deadwood, just like you said! It can't possibly be worse than this.
But Frux just glances between Muts and the horrible black growth that's consuming half the warren's surface, and when she turns back to Muts he can see from her expression that she's not coming.
Muts (furious, turning away): Fine!
Frux: Muts, wait--
Synx (interrupting) Let him go!
Synx (cont'd, addressing the others): And anyone else who wants to join him. You'll all be dead within the hour.
Synx watches Muts defiantly march towards the black forest, despite what she just said we can see from her expression it bothers her.
Synx (yelling after Muts): Running away won't change anything!
But Muts doesn't turn back as he disappears into the black forest.
Wrex (approaching Synx cautiously, low voice, imploring): You know he's too valuable to lose.
Synx exhales deeply, brooding, we see her turn to Vox who stares back at her.
Meanwhile, one of the cubs in the group who is less scared than the others asks his father (one of the soldiers) a very practical question.
Cub: What happened to the bodies?
I'm thinking about at the end of this scene, Wrex tells Muts "Please don't" and Muts stares back at him defiantly, and Wrex thinks that there's a fire in the eyes the rabbits could never hope to contain, that other person was right, they could never control him. Also perhaps we describe Muts' fear as he approaches the dark treeline, like even looking at the trees seems to sap the life out of him, but he overcomes his fear and goes anyway, even when Wrex makes him hesitate.
Perhaps when Muts enters Wrex yells "Wait!" and tries to go after him but it stopped by Vox, and that's why he has to convince Synx. He goes up to her but then the guards step in and he stops before he's in range to actually hurt her, and pleads with her.