. "Sonar Net (CivBE)"@en . "The Sonar Net is an aquatic only building that was introduced in the Rising Tide expansion pack. This building provides +25 City Defense, and it reveals invisible units with 2 tiles"@en . . "The Sonar Net is an aquatic only building that was introduced in the Rising Tide expansion pack. This building provides +25 City Defense, and it reveals invisible units with 2 tiles"@en .