by Dumon
Quick answer:You unfortunately got the card text wrong. If you block your opponent, YOU lose prestige. Only exception: If you got ten galleys in the specified areas...
But other than that, I think you are right. Although I would not deem it a 5th way, but an enhancement of the 4th.
So maybe we should put in the FAQ:
Whenever a player HAS to lose PP, but is already at 0 PP, this unavoidable loss will result in him losing the game!
Okay, that was a bit inelegant, but it states the point, I guess...
;)