Battlefield 4 really does contain a dinosaur Easter egg which when triggered will make everyone in the server go “WTF?”
The Easter egg is in the Rogue Transmission map, which also has a whole scene laid out from Jurassic Park. There’s a caged goat, along with the accompanying vegetation terrain which makes you recall the T-Rex scene from the movie. The Easter egg is related to this but unfortunately you won’t be calling in a mighty T-Rex.
On the map are two hidden buttons, which when triggered simultaneously by two players, will play a a sound clip of a roaring T-Rex that will fade away, echoing throughout the valley. Everyone on the map will hear that. To add to it, some of the trees on the horizon will also start shaking and shift, as if the T-Rex is charging through.
YouTuber JackFrags has a detailed video above which you can see to learn the exact spots of the buttons.
There has been another rumor that beneath the waters of Paracel Storm, lies a Megladon, a huge shark, but that still remains to be seen.