Babylon 5: A Call to Arms (ACtA) is a tabletop miniatures boardgame released in September 2004 by Mongoose Publishing, designed initially as an expansion to their Babylon 5: The Roleplaying Game, it is a complete game in its own right. Babylon 5: A Call to Arms is based upon the sci-fi television series Babylon 5 and draws heavily on material from the television show and the boardgame Babylon 5 Wars.