Hey there: fairly new to dominionstrategy.com, but been on isotropic for a while. I thought I'd share with you one of my favourite Ambassador based combos. As far as I can recall, I've had an excellent success rate pursuing this strategy whenever the cards have come up.
This is more of a strategy and synergy than a direct combo: the goal isn't to draw these two cards together, but to play them in the same deck.
Ambassador / Ambassador is a favourite opening of many, and the traditional way to play it is with
Big Money.
It works well with
Fool's Gold for the following reasons:
Firstly,
Ambassador makes for thinner decks. With two
Ambassadors, ideally sending away two cards each time they are used, you'll have a shrinking deck even if you're being
Ambassadored back. Clearly, for
fool's gold to work, either a thin deck is needed, or drawing power.
Second, because it costs only $2, you can often buy
Fool's Gold on the same turn that you activate the
Ambassador, so this is a quicker climb than going silver --> gold.
Third, if your opponent goes for the same, and grabs a province before you, you can react with
Fool's Gold, trashing them to put gold on your deck. Personally, I don't often use this option, as a turn's delay is too long in most cases. But in the specific circumstance of a hand of less than $8, where your opponent is competing wiht you for fool's gold, and has bought a province, I would take the trash-for-gold. If you REALLY want to, and if you're well ahead, you could even speed the game's conclusion by sending a Province over with Ambassador, and then reacting to turn the
Fool's Gold to
Gold!
Here's an example of a game where the combo worked well for me. Its a slow finish, but Ambassador/Ambassador always trades speed for control. I had bought 4 provinces by the end of Turn 16.
http://dominion.isotropic.org/gamelog/201201/20/game-20120120-112112-1c88e5e4.html