Nightjars hunt at dusk. Hand after hand, you must say exactly how many tricks you will take, not as many as possible. Say three and take three: a good hand. Say three and take four: a bad one.
The cards
Four dusk suits, each from 3 to 10:
moth ,
beetle ,
mayfly and
cricket .
On top of those are four nightjars (I to IV), which are always trumps.
Not every card is dealt, so you can never be sure what is still out there.
A hand
Everyone is dealt the same number of cards, and the hands grow then shrink: 2, 3, 4, 5, 6 and back down again. A game is 8 to 10 hands, depending on how many are playing.
Predict. Everyone privately picks how many tricks they will take, from 0 up to the size of the hand. All the predictions are revealed together, so nobody can hide behind anyone else's choice.
Play. The leader plays a card; everyone else must follow that suit if they hold it, and may play anything if they don't. The highest nightjar wins the trick; if there is no nightjar, the highest card of the suit led wins. The winner leads the next trick.
Scoring
Exactly right, having said 1 or more: 10 points, plus 5 for every trick you said.
Exactly right, having said 0: 3 points for every card in the hand: slipping untouched through a big hand is the prize; ducking a small one is only a consolation.
Wrong: −4 for every trick you are over or under.
After the last hand the highest score wins. A tie is shared.
Tips
Saying 0 is a real choice, not a surrender. But a high card you cannot get rid of will ruin it.
Count the nightjars. Only four exist, and they may not all be in play.
Once you have taken what you said, start losing tricks on purpose.
Playing friends
Tap ⋯ → Play friends online and send the link to 2–4 friends (3 to 5 at a table). The cards are dealt and held by the server, so nobody can see your hand.
On this screen
The other players sit across the top: their name, how many tricks they said, how many they have taken, and how many cards they still hold.
The trick sits in the middle. Your cards are at the bottom: the ones you may legally play are the bright ones.
Tap a player to see their hand's record. ⋯ → Game info has the scores and what happened.