Kepler & K2 provide long-baseline, high-precision photometry for exoplanet and astrophysics research.
The basic and most common additional rule for Doubles play is that where a Double exists at the end of any train, the Double must then be 'satisfied' (laid against) in the next turn, even if the Double is on another player's train that is not marked.
Mexican Train is a game played with dominoes. The object of the game is for a player to play all the dominoes from his or her hand onto one or more chains, or trains, emanating from a central hub or station.