Hidden movement, patrols and imperfect knowledge in naval wargaming

The game separates each side's knowledge from the umpire's complete record. The umpire logs moves without automatically revealing them to the opponent. A search ring or other contact is required to discover hidden movements. Separate maps show what each player knows and what the umpire knows, preserving uncertainty about enemy positions. Each power has a limited number of patrols and must choose where to establish presence. One raiding group encounters almost every patrol and falls into an ambush, while two later groups are held back and deployed together. Search coverage and the timing of concentration both affect the result.