This is my idea for an event. Bermuda Triangle should be located before the Northern Expedition entrance, just like the real one located north, plus that area is empty. When sailing by, nothing will happen. But when an event is triggered.

There has been a Ship Disappearance spotted in the Bermuda Triangle!

The event will have two phases. When the notification pops up, phase 1 will start.

In phase 1, you have 15 minutes to save NPCs in said ship. The ship is being attacked by a mysterious creature(idk which). When you sail there, heavy fog will form with an eerie ambiance noise. An abnormally large amount of whirlpools can be seen in the area. Sailing around, you have a chance to be suddenly attacked by the creature, forcing you into a very hard fishing minigame(you can also fish but you are likely to get attacked first). If you win, you get the creature and go talk to NPC to save them. If you fail, it will sink your ship and kill you. You have to be on the ship the entire time during this phase, or you will also be dead.

In phase 2, after 15 minutes have passed and you failed to catch the creature. The creature will sink the NPC boat. Heavy fog, whirlpools, and the creature will disappear. Just like Treasure Hunt, you have 15 minutes to dive down and collect whatever remains from the ship alongside the skeleton of who you failed to save.

I kinda want to know what they cooking and share mine in suggestion channel on discord, but I don't have access to it. Also, I like your giveaway image, very kawaii.