Just like in Monster Hunter World, Iceborne has a bunch of mystery pets and fish for players to find across the map to add to their collections.

These creatures are usually rare spawns, and the one we are going to search for today is no exception. We are going to show you exactly how to get the Achievement “Submerged Mystery” which is a secret achievement that can be completed by completing the mission “Capture a mysterious creature lurking beneath the water’s surface.”

To do this, you need to find the Sealord’s Crestfish, a large fish that can be located only at night in the Hoarfrost Reach. You can find it in the pool of area 8 at times if you are lucky and can’t miss it. It is a large fish, larger than anything else you can see in the pool, with a strange shark-like fin sticking up out of the water.

Finding it when it spawns is easy, but catching it is hard. You will need to go through a series of mini-games and test your nerve not to scare it off. If you do, you will need to repeat the whole process and pray you to find it another time.

Considering it can take hours at a time to come across this fish, don’t do anything stupid and be sure you are ready before you try to capture it. You only have one shot.