Horrors Below

 is a Sunless Sea Random Event. It has a chance of 1% to come up.

Trigger conditions
 is triggered at zee if you have the following:  Terror ≥ 50 and ≤ 75 

Event description
Zailors at the rail call softly. Something swims beneath the ship. “I saw it looking up at us!”, one says, his voice a-tremble.