New stars and alien species have been discovered in the galaxy! Will you exploit the new Viliox species to destroy your foes or befriend one of the new starting ally species to explore the new stars? Horizons: Extermination adds five Viliox Alien Ally cards, five alternate Starter Ally cards, and six alternate Star tiles. The Viliox add conflict, destruction, and extermination to Horizons. The alternate Starter Allies add more variety to the beginning of Horizons. The alternate Star tiles have special powers, benefits, and constraints.