Can we, uhm, get the official FAQ for Sauna/Avanto?
Is there a question you want answered?
Well, I see the FAQ as mostly just covering questions a player not as versed in Dominion arcana as we are might have. So they might wonder if they could play the Avanto for free later in their turn if they already played a Sauna, rather than just right away. Or if you Crown a Silver, if that means you can trash two things with Sauna. Or if they'll have extra Actions after chaining Sauna-Avanto-Sauna-Avanto-Sauna.
This.
"When you play Sauna, you first draw a card and get +1 Action. You may then immediately play an Avanto from your hand. This does not take up one of your actions, including the action provided by Sauna. You can only play an Avanto this way directly after playing the Sauna, not if you played another action card inbetween, even if you have a Sauna in play.
When you play Avanto, you first draw 3 cards. You may then immeditately play a Sauna from your hand. This does not take up any of your actions, and Sauna will still give you +1 Action if you play it this way. You can only play a Sauna this way directly after playing the Avanto, not if you played another action card inbetween, even if you have an Avanto in play.
You can play Sauna and Avanto in alteration this way, taking up only the action for the first of the cards you play. You can do this until you don't have the respective card in hand after playing the other. When you play a Sauna, you can not immediately play a Sauna from your hand without using up one action. The same goes for playing Avanto after Avanto.
While Sauna is in play, you can trash a card from your hand anytime you play a Silver. If you play the same Silver several times, such as with Counterfeit (Dominion - Dark Ages) or Crown (Dominion - Empires) you may trash a card each time you play the Silver. You do not have to trash anything when you play a Silver. You can decide to trash a card every time you play a Silver, you do not have to decide once for the entire turn. When Sauna leaves play, such as being trashed with Procession (Dominion - Dark Ages), you can not use its effect anymore. When you have several Saunas in play and play a Silver, you can trash a card from your hand for every Sauna you have in play. You can still decide to not trash a card each time."
Wow, this turned out long. We need professional FAQ-writers...