Jump on board the good ship Tranquility and set sail for paradise. Take care, though, because in a land where the day blends into night it's easy to lose track of time and you still need to find that special little island to call home.
Tranquility is a co-operative card game in which players must fill the sea with islands — specifically island cards with numbers on them — and guide the ship home before any player runs out of cards. Note that in the world of Tranquility, the only way to play is in silence.
In more detail, the island cards are numbered 1-80 and are distributed equally among the 1-5 players. You will play island cards into a 6x6 grid, and the cards must go from low in the bottom-left corner to high in the top-right corner, with numbers ascending along the bottom row from left to right, then the second-most bottom row left to right, and so on. Players start with a hand of five cards.
On a turn, either you discard two cards from the game, then draw two cards, or you play one card somewhere into the grid following the placement rules. If you play a card that's adjacent to one or more other cards — even if above or below a card — then you must discard cards from your hand equal to the difference between the number on the just played card and whichever card would make the smallest difference. If this difference is more than four, then you can't play this card.
Each player has a "Start" card shuffled into their deck, and if you have one in hand and one hasn't been played, then you must play it into the corner to the lower left of where the first number card will go, then all players must collectively discard eight cards from their hands. Subsequent "Start" cards can be discarded from play as with any other card. Five "Finish" cards are shuffled amongst the island cards, and once the 6x6 grid is finished and a "Start" card in place, the next player must play a "Finish" card to win the game. (Until that time, of course, they might just choke up your hand.)
—description from the publisher