Arctic explorer

Discover the polar region
· You can unlock this secret achievement during Chapter 7 in the same area as the blue whales (Leviathan). In the corner of the map, there will be a small island of ice with penguins and a polar bear. Simply climb up onto it.

Connection

Ride the Great White Shark
· You can unlock this secret achievement at the beginning of chapter 7. You just must swim up to the Great white shark.

Kraken

Discover those that lurk in the abyss
· You can unlock this secret achievement as early as chapter 4, but also in the chapter 7. You just must swim up to the giant squid and ride it.

Leviathan

Breach the water on the back of a blue whale
· You can unlock this secret achievement during the seventh chapter. When you enter a large open area with gigantic blue whales swimming around, you should mount some and try to steer it to the surface and then press boost to create a breach in the water.