Sidereal Confluence: Trading and Negotiation in the Elysian Quadrant is a unique trading and negotiation game for 4-9 players. Over the course of the game, every race must trade and negotiate with the rest to acquire the resource cubes necessary to fund their economy and allow it to produce goods for the next turn. Scheming, dealing, and mutually beneficial agreements are the keys to success. While technically it is a competitive game, Sidereal Confluence has a cooperative feel during the trading phase as no race has the ability to thrive on its own. Trade well, and you'll research technologies and colonize planets to form a civilization that is the envy of the galaxy.

Each player picks one of the nine unique and asymmetrical alien races that have come together to form a trade federation in their quadrant. Each race comes with its own deck of cards representing all the existing and future technologies it might research. Some races will also have other cards related to unique features of their culture. These cards represent portions of the culture's economy and require spending some number of cubes to use, resulting in an output of more cubes, ships, and possibly even victory points. Since each culture's outputs rarely match their inputs, players will need to trade goods with one another to run their converters to create the resources they truly need to run their society most efficiently and have an effective economy. Almost everything is negotiable, including ships, colonies, and all kinds of resources.

Each game round has an open trading phase in which all players can negotiate and execute deals for cubes, ships, colonies, even the temporary use of technologies! Players who have enough resources can also research technologies, upgrade colonies, and spend resources on their race's special cards during this phase. Once finished, all players simultaneously run their economies, spending resources to gain more resources. The Confluence follows, starting with players sharing newly researched technologies with all other races and following with bidding to obtain new colonies and research teams. Researching a new technology will grant many victory points for the prestige of helping galactic society advance. When one race makes a new technology, it is shared with everyone else. Technologies may be upgraded when combined with other technologies.

The ultimate goal is victory points, which are obtained by researching technologies, using your economy to convert resources to goods, and converting your leftover goods into points at the end of the game.

The game consists almost entirely of simultaneous play.

Sidereal Confluence: Remastered Edition features the same gameplay as the first edition of the game from 2017, but contains an updated card layout, a teaching guide, and an improved rulebook for easy set-up and learning with more visual examples and clear key terms.