This seems like a really obvious question, but I can't actually find in the rules what happens to a card attached to an enemy after the enemy dies.
I don't see it mentioned under "Eliminating Enemies", "Attaching Cards", "Enemy Elimination", "Attachment", or "Discarding and Burying Cards".
In fact, under "When to Discard Cards" (p18) it specifically says "Cards may only be discarded or buried when a game effect allows or requires you to do so."
As far as I can tell, there's no explicit effect or text that discards or buries a card after it has been attached.
So... which text am I just missing? It's gotta be somewhere