Dark spots that are present on the sea usually predict evil and dangerous conditions, supernatural events, and killing sea creatures. The most deadly sea spot is: 

1. Bermuda Triangle (Atlantic Ocean) 

Also called the "Devil's Triangle," this water body between Bermuda, Florida, and Puerto Rico lost several vessels and aircraft in the mist of mid-air disappearance. The cause of such an experience is anomalies like magnetic or supernatural activity.

2. Pacific Ocean Mariana Trench 

It is one of the deepest points on Earth; its depth stretches up to 36,000 feet. Extreme pressure and complete darkness make it the unexplored part of the ocean. 3. Cape Horn Southern Ocean: This is the bottom of South America where winds slap the oceans, enormous waves, and capricious climatic conditions are found. It is a nightmare for any sailor to sail in this region. 

3. Somali Coast of the Indian Ocean 

This is a region where piracy is mainly conducted. Most ships are hijacked while passing over water. This has become one of the most dangerous regions to pass through. 

4. Great Blue Hole (Belize)

This is an enormous hole underwater and is horror fully beautiful but fatal. Impulsiveness and wrong measurement have led to several fatal diving accidents. 

5. Dragon's Triangle (Pacific Ocean)

This Pacific off the coasts of Japan has oft been termed the "Devil's Sea" and is said to be the Pacific equivalent of Bermuda Triangle with an abnormally gigantic number of unexplained losses of ships and aircraft. 

6. Cocos Island (Pacific Ocean)

The waters around this island lie off the coast of Costa Rica and pose problems to divers as there are deadly sharks coupled with unstructured ocean currents. 

7. Point Nemo (Pacific Ocean)

It is a pole of inaccessibility because it is furthest from any land mass. Such points are very dangerous for sailors or researchers since they are impossible to be rescued near.

 Those are dangerous tourist spots, interesting to adventurers and scientists alike, carrying along the mystery of the ocean and the dangers.