Here are my thoughts on how to deal with everyone known to be in or near that final room...
Dolo - Kick his arse spiritually, and then if his body isn't destroyed or incapacitated as a result then go and make sure that it is - physically he looks as though he'd be an absolute pushover if taken by himself as he seems very weak and frail. It's his mental powers and wandering spirit that do the damage.
Garax - As I mentioned, Haynuus and I nearly took him down before, just the two of us. He's tough, but not excessively so, and might still be weakened from that earlier encounter. If Dolo is taken care of he'll have lost his main (and possibly only) ally so his morale will be demolished

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Dargat - Currently an unknown quantity. I presume he's much tougher than Garax. I don't know of any special magical abilities he might have but he sounds like a bit of a tank, physically. I'll need to go through the PMs Wuffy sent me months ago (when Ameena was in the other timeline or something and got all these memories of these people) and see if I have any more detail on him.
Gholst/Theron - I reckon we need to talk to Theron. We need to persuade him to let Karnadee go, which will mean Gholst has no further hold over him and Theron can therefore kick his arse. It might also be an idea to mention that he's got one of the Soulstone pieces, that Gholst hid it on his person somewhere (again, I'll need to check my PMs to see if I have any further info on the location)...though probably best not to say anything about it while there's a chance Gholst can then take over and try to kick our arses or something.
Passin - Yeah, remember he's up there too

. We don't know if he's tried to back out of being a Blackskull or something. He might be telling the uber guys all about us, or he might be about to be killed by Dargat so Dolo can put his soul into the Blackskull armour or something. For now I suppose he's another unknown quantity.
Regarding the Soulstone - remember there are two pieces left. There's the largest chunk, which I think was possibly in some way in Dargat's possession, or might just be in its stand thingy up in that top room - it would be good if we could find this out, but maybe the fish-ball* can help us there. I'll see about giving it a try if Westy doesn't turn up anything. And the final Soulstone piece, as mentioned, is in the possession of Gholst/Theron but without the latter's knowledge.
Whatever happens, I recommend we
do not fully rebuild the Soulstone until Gholst is dealt with - otherwise we might just end up repeating what happened in the First Run. It would probably be best not to even
hint that we've got half the Stone on us in front of Gholst. He might get a bit...funny about it.
Oh, and as for the grak-graks...hmm, well, Dolo doesn't have complete control over them like Soorec did. It probably won't even take killing Dolo for him to lose control - just distracting him enough might be likely to do it. And, you know, if we distract him when he's standing between us and at least one grak-grak, I reckon that he might possibly find out rather quickly what Soorec felt like in his last moments

. We should probably be careful, though, that we don't take out Dolo and then have the grak-graks gatecrash our imminent victory while we're finishing off Gholst or something

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*Yeah I know it only had a fish in it that one time but I can't think what else to call it

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