NavalBattleZone: High Caliber is a Java 1.21.1+ server focused on WWII-era naval combat. Build and command warships like battleships, aircraft carriers, and submarines, using radar, sonar, and hydrophones to track enemies above and below the surface. Customize ships with working turrets and cannons, deploy AI crewmembers to operate systems like turrets and radar, and fight AI-controlled ships. A factions update lets groups form, wage war, and compete for control of strategic sea locations, with no mods required to play (OptiFine or Fabric Sodium recommended for performance).