I just got the Race for the Galaxy: The Brink of War expansion and it adds Prestige mechanics to the game. Those I understand. The Prestige Leader mechanic, however, I don't understand and the rulebook isn't too clear. Why is it there? How does it work?
The instructions in the rules are pretty clear if you read them and follow them directly. If it helps, it pretty much boils down to:
- if there's a single prestige leader, and they gained prestige last turn as they became prestige leader or afterwards, they get 1VP and 1 card
- if there's a single prestige leader, but they only gained prestige on earlier turns, they get 1VP
- if there's a tie for prestige leader, all tied players get 1VP
In practice, the condition for getting 1VP and 1 card (the first bullet point) is pretty much always equivalent to whether the sole prestige leader gained prestige on the previous turn. The only time it's not is if, say, they became prestige leader during Develop, they lost it/became tied during Settle, and they became sole leader again during Consume; that's of course quite rare.
In order to remind yourself of all this, you pass around the prestige leader token. Whenever there's a single leader, they get that token, and they put any prestige they gain on it as a reminder that next turn they'll get 1VP and 1 card. When they get that bonus, they take their prestige back as a reminder that next turn they'll just get the 1VP. When there's a tie, you flip it over to the tie side, and the former leader takes back their prestige, as a reminder that it'll just be the 1VP bonus next turn.
And... the point of this is to provide small ongoing rewards for prestige! In some cases, it's even enough to make prestige a good overall plan for your game.
When one player has more prestige tokens than any other player at the start of the round, he gets the Prestige Leader token. Any Prestige earned during the round goes onto that token. At the start of the round (before selecting phases), the leader removes the Prestige from that token (putting it with the rest of their Prestige/VP), earns 1 VP chip, and draws a card. If, at the start of a round, the Prestige Leader has no prestige on top of the token (i.e. they didn't earn any new Prestige last round), they still get the 1 VP chip, but do not draw a card.
If two or more players are tied for the most Prestige at the start of a round, then they all earn 1 VP chip. No cards are drawn in this case.
In my estimation, the Prestige Leader mechanic is there to ensure that Prestige doesn't become nothing more than a different color of VP chip, and to reward players who continue to earn Prestige throughout the game.