A thrilling and tightly paced, albeit fairly predictable run against time. The moment the cards were laid on the table and we learned that Ruhn needed the bloodline to support his bid for the throne, L'ak's fate was sealed, as was the conclusion that Moll would set the universe on fire if she couldn't be together with him, or would destroy everything if it meant getting him back. Still, the episode proved quite adept at portraying the anxiety and tensions, making me feel like a war could indeed break out at any moment, and even the comic relief scene of Reno providing the crucial clue for the metal card ended up being interrupted by Ruhn arriving earlier than expected. I was so much on my toes that I even thought it entirely possible that the Primarch would casually mention that his rival Tahal was dead all along. Needless to say, the Federation had two choices, both of them bad, so I have to agree with T'Rina's logic that buying time is still the less bad one.
We learned quite a bit about Rayner today, with the story of his family being killed by the Breen providing some great context to his personality and worldview, although he initially seemed to be thrust in a similar role as General Ndoye was in Season 4, as a contrarian seemingly solely for the sake of being a contrarian. I did like however that he ended up showing a degree of introspection, admitting that his harrowing experiences influence his thinking, and helped out with the negotiations anyway, with his history with Tahal being used to build up the illusion that the Federation had been in contact with her.
And we're going to the Badlands, people, yaaaay! And not just the Badlands, as Book's vision seemed to impart the word 'eternity' as well, so we might even be visiting a certain wormhole in the vicinity as well?
Edited for my brain fart with the other primarch's name