Submarine naval battle

# Sonar of a submarine and a patrol aircraft, it senses enemies and destroys it.

# Enemy submarines, patrol aircraft are not displayed on MAP.
# When an enemy ship is detected in the sonar region of your army, the approximate position is displayed.

# In log mode, you can check the position, behavior and status of enemy ship, patrol aircraft every turn.

# The win / loss condition depends on MAP.
1. Defeat the flagship
2. Number of areas in sonar search area
3. Number of mine sweeps
4. Inhibiting entry of enemy submarines
5. Reaching the goal of self flagship etc.