Torpedoes in Dangerous waters are great. I've seen/done everything above surface from drop a torpedo into 175 foot deep by 200 square foot window of water in an ice sheet to sink a sub a mile away. To even having a torpedo get confused between my FFG and the enemy sub.
A skilled pilot/remote helo controller (manual helo from FFG) can use 1 torpedo to kill you without you having any warning until you hear the sonar operator scream "Torpedo in the water!!!"
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