Battlefield 4's newest DLC, Naval Strike, has brought refreshed gameplay for this at times struggling title and has added in a host of new features and modes. Now, players can get excited about the game's "secret assignment."

According to Kotaku, there is hidden mission called "Phantom Trainee." To unlock it, the gamer needs to create a fake player, use morse code, learn the viking alphabet, and take various other steps. A YouTube video has been released that provides a guide on how to Phantom Trainee. See the instructional video at the bottom of the article.

Watch how to unlock Phantom Trainee below:

For Battlefield 4, one of the biggest "Easter Eggs" that has been getting attention is the inclusion of the Megalodon Shark.

While fighting in the water the huge shark can be seen jumping and launching itself through the water with a loud roar and explosion. The shark obliterates everything it its path.

According to Polygon, Megalodon was hinted at in December when messages appeared on Reddit, providing details and a few screenshots.

Also, Battlefield 4's Naval Strike DLC will be launching on April 15 for non-premium members announced a tweet by the video game's social media account last week.

The expansion previously came out on March 25 for the PS3, PS4, and Xbox 360. The Xbox One version was launched on the 28th because "issues in the animation system that hinder players from engaging targets in set circumstances using popular weapon configurations," DICE wrote on their site. Lastly, the PC version was released on March 31. These were all made available to premium subscribers.