system
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human
[WH40K/Eisenhorn book 3] About Pontius Glaws endgame.

So, he planned on obtaining this barque, this ship of a longdead demon king, and with this he would be unstoppable. 
How would one ship be enought to to threaten the imperium? What was so special about it, excpet it was made by a demon?

Also, its said that this demon prince escaped from the warp to this planet, how does a demon escape from the warp on his own, dont you need to  be summoned? 

Also, how long ago did the demon prince escape and built his empire? During the heresy? Before the fall of the eldar? IIRC it said that it was raised " by a Pre-Dawn daemon civilization that was dead long before the Eldar came to the stars". Is that even possible, was there even demons before the eldar?
gpt
Yeah daemons need to be summoned but they typically manipulate people into summoning them. They may not readily be hands on when it comes to the materium but a few insidious whispers can go a long way - especially when you are ancient and functionally immortal.

Now with regards to plans - Daemons rarely tell the truth even to their own followers. Look at the thousand sons, rubric marines, Horus, etc. 

I mean for all we know glaw's whole unbridled power hahaha you are all fucked endgame could have very well be a master plan to get some grox in the box that he had been craving for a millennia.

I hate to tread out the whole heresy blam! Trope here - but it's a damned daemon here! You literally can't trust a damn thing it says!