Star Trek: Catan takes two well-known media properties and merges them into, well, into something that is 95% The Settlers of Catan glossed with Trek tropes and spiced with new special powers related to Trek personalities.
In Star Trek: Catan, players start the game with two small Outposts at the intersection of three planets, with each planet supplying resources based on the result of a dice roll. Players collect and trade these resources:Dilithium, Tritanium, food, oxygen and water in order to build Starships that connect regions in the galaxy, establish more Outposts and Starbases (upgraded Outposts) at new intersection points in order to increase resource acquisition, and acquire Development Cards that provide Victory Points (VPs) or special abilities.
On a dice roll of 7, a Klingon ship swoops in to prevent resource production on one planet, while taxing spacegoers who hold too many resources.
The one new element in Star Trek: Catan compared to the Settlers version is a set of "Support Cards", each featuring one of Kirk, Spock, McCoy, Sulu, Scott, Uhura, Chekov, Chapel, Rand or Sarek. Each Support Card has a special power that the holder can use on his turn, such as a forced trade. (Some can be used out of turn, such as Kirk's "Protection from the 7" ability.) Each can be used either once or twice by a player before being returned to the "Support Card Pile" and replaced with another Support Card of the player's choice.