ok hold on hold on i'm very confused. were arsenik and ambrosia a thing already back then or is this like an alternative version of the tale from beauty and war??? I'm so lost
Ah, yes. This was the complicated one! It's completely understandable if it takes your head for a spin. My answer to an ask here might help clear things up. (Warning: Has major spoilers!) There's also a rather helpful TVTropes page, I believe.
Now, if you're interested in learning more about the world of Beauty and the War (X Playing Pieces) without the psychological craziness, I might suggest playing War: Valentine Edition instead. Trust me, it's far more straightforward, very sweet, and a fan favorite. That is, if you like romantic comedies.