Eggraging shark of the sea was an item that you could only obtain in the Sharkbite Easter event 2020 (sometimes called the 2020 egg hunt). In order to obtain it, you would have had to grab the key to the egg hatch which is floating on a buoy. The buoy is attached to the shark. It was useful to have a boat that will make the shark lag (such as a titanic or deluxe yacht) so that it would become much easier to get the key on the buoy. Once the player got the Event key, they could use it to unlock the Easter Hatch. They could have gone inside the hatch if they unlocked it with a key.
If the player had touched the Eggraging shark of the sea egg for the first time, they would have received a badge and an Eggraging shark of the sea, and the Egg emitted purple sparkles and floated up into the air.