Keyflower is a board game for two to six players played over four rounds. Each round symbolizes a season: spring, summer, autumn, and finally winter. Every player starts the game with a "home" tile and an initial team of eight workers, each of which is colored red, yellow, or blue. Workers of matching colors are used by players to bid for tiles to add to their villages. Matching workers may alternatively be used to generate resources, skills and additional workers, not only from the player's own tiles, but also from tiles in the other players' villages and from the new tiles being auctioned.

In spring, summer and autumn, more workers will arrive on board the Keyflower and her sister boats, with some of these workers possessing skills in the working of the key resources of stone, iron and wood. In each of these seasons, village tiles are set out randomly for auction. In the winter no new workers arrive and players select the village tiles for auction from those they received at the beginning of the game. Each winter village tile offers VPs for specific combinations of resources, skills and workers. The player whose village and workers generate the most VPs wins.

Keyflower presents players with many different challenges and each game will be different due to the mix of village tiles that appear in each game. Throughout the game, players need to be alert to the opportunities to best utilize their various resources, transport and upgrade capability, skills and workers.