|For each card you've gained this turn, you may trash a card from your hand or a Copper you have in play.|
 Official FAQ
- For example if you have gained three cards, you may trash up to three cards, with each being either a card from your hand or a Copper you have in play, in any combination.
- Normally, bought cards are then gained, but cards exchanged for (such as Vampire exchanging for Bat) are not gained.
 Other rules clarifications
- Cards are trashed one at a time. This matters if one of the cards you trashed draws another card; such cards drawn in the middle of trashing can be trashed by Monastery.
- Gaining cards while you trash to Monastery (for example, if you trash a Hunting Grounds) does not let you trash additional cards; you can only trash a number of cards equal to the number of cards gained that turn prior to playing Monastery.
Original article by Chris is me
Monastery is a far more powerful trasher than it may appear to be at first glance. An obvious point of comparison is to how Forager plays in the early game. Like Forager, Monastery does not take an Action, trashes Estates for no (other) benefit, and trashes Coppers without hurting your economy for that turn. Where Monastery shines is that it allows you to trash without sacrificing any momentum (beyond drawing the Monastery) — you don’t give up economy, you don’t have to worry about drawing it dead, and it even trashes faster when used in tandem with gainers or +Buy.
Monastery’s properties allow for more aggressive openings than one would typically do with a trasher. Consider an opening of Smithy / Forager. Normally this is a bit risky – the Smithy could dead draw the Forager, wasting a shuffle’s worth of trashing. Since Monastery is played after the Buy phase, it can’t be drawn dead like Forager in this situation. In addition, you get all of the benefits of Smithy’s extra cycling and economy, leading to more frequent trashing and faster gains. This can quickly snowball into a very potent deck that trashes seemingly without effort.
The synergy with gainers such as Ironworks or Engineer are obvious – gain a card, ideally buy another card, use Monastery to trash twice as much as you normally could. But this synergy often enables even weaker cards such as Silver gainers which you may not otherwise consider. Squire is an interesting example, where it can gain Silvers early to give Monastery an extra trash, provide multiple Buys later for a similar purpose, and can even be turned into an Attack card if need be.
In games where you need to get very thin very quickly, opening two copies of a trasher is often wise, but that is usually incorrect with Monastery because if two copies of Monastery collide, you may not be able to gain a desirable card which sacrifices momentum. You do often want two copies of Monastery, but try to stagger buying each Monastery with buying more aggressive cards that draw or gain to keep things moving. The main takeaway from this is that you should adjust how you pace your deck when using Monastery instead of other trashers. Play to the strengths of Monastery, and you will be very glad you picked up this unique trashing card.
 English versions
|For each card you've gained this turn, you may trash a card from your hand or a Copper you have in play.||Nocturne||November 2017|
 Other language versions
|German||Kloster||Pro Karte, die du in diesem Zug genommen hast, darfst du ein Kupfer, das du im Spiel hast, oder eine Handkarte entsorgen.|
|Japanese||修道院 (pron. shūdōin)||このターンに獲得したカード1枚につき、手札1枚か、場の銅貨1枚を廃棄してもよい。|
|Russian||Монастырь (pron. monastyr')|
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