What is his endgame?

What is his endgame?

To keep playing the game forever.

And to be on top forever

Didn't he get totally shown up in GS? Like everything fell apart and he failed totally?

IIRC my Dark Eldar lore correctly, whenever Asdrubael Vect is involved in a war and loses, that typically means that he wanted to:
1) Get rid of some uppity warriors within his own ranks
2) Deliberately got involved in a very bad war and made sure some of his political enemies lost more troops than he did

3) He's pretending to be weak by losing a few wars, emboldening his enemies (which are pretty much everyone in Commoragh) to strike after which he pulls a "I was merely pretending to be retarded".

Pretty sure GS2 has him furious with his losses, Malys leading the Archons in talks of killing him, Urien fucking off, and the Mandrakes saving the day and consuming half of Commoragh after gaining a huge power boost.

Very sure it even has a line about how his plan for dealing with the Dysjunction isn't working, hence why the Mandrake+Haemonculi team up saves them.

Pretty sure pic related delivered the war in his living room, not that he chose to get involved.

Well
>3) He's pretending to be weak by losing a few wars, emboldening his enemies (which are pretty much everyone in Commoragh) to strike after which he pulls a "I was merely pretending to be retarded".

But there's been no indication anything was pretend at all. And it says he's genuinely pissed off and that things didn't go as planned.