Race for the Galaxy: Alien Artifacts

Race for the Galaxy: Alien Artifacts, an expansion for Race for the Galaxy, is incompatible with earlier expansions for that game, instead taking the game in a new direction. According to a forum post from designer Tom Lehmann, Race for the Galaxy: Alien Artifacts consists of two parts:

~45 new cards and start worlds to add to the base set, plus a set of action cards and start hand for a fifth player.

~45 cards and Alien tokens used to represent the Alien Orb which players jointly map and explore, gaining tokens of various types that provide powers and VPs. There are also five new Explore action cards used to map the Orb (instead of gaining an additional card or greater card selection).

The Alien Orb scenario provides a new RFTG experience, as players have to balance how much effort, resources, and actions they wish to put into exploring the Orb versus developing their empires.