Race for the Galaxy Alien Artifacts is the fourth expansion for Race for the Galaxy is incompatible with earlier expansions for that game instead taking the game in a new direction Race for the Galaxy Alien Artifacts consists of two parts 46 new cards including 5 new start worlds to add to the base set plus a set of action cards & start hand for a fifth player These can be used without the orb cards 49 cards used to represent the Alien Orb which players jointly map & explore gaining artifact tokens of various types that provide powers & VPs There are also five new Explore action cards used in the orb game (instead of gaining an additional card or greater card selection) The orb game is optional & provides a new RFTG experience as players have to balance how much effort & actions they wish to put into exploring the orb versus developing their empires