All your recent adventures were about stopping villains from creating chaos on File Island. But few parts of the Digi-world were explored by your and your team, especially the vast Net Ocean. It is said that during this time of the year many water Digimon rise form the dark abyss near the surface, but the meeting place is an extremely remote point in the middle of the eastern part of the Ocean.
Nonetheless, your team is excited to go on a cruise and meet these mysterious Digimon, especially since you would all board a real ship and not a flimsy raft like the last time you battled the waves.
After some short preparations, your cruise leaves the port at dawn and you settle in, enjoying the autumn sun and salty sea-breeze. Not only this, but you have time to catch up with some friends that are also travelling with you. However, they fear the deep-sea Digimon for they're not used to visitors. But this is no impediment to you, as Submarimon is a dear friend and it must be able to introduce you to its friends.
Arriving that the supposed location with the help of the cruise's captain, she provides you a small boat with enough fuel and equipment to last until the ship's return. After making the necessary preparations, all your team is ready to plunge into the unknown! A continuous ping detects Submarimon's position, and you all head there, straight down between coral-filled crags.
"Tamer, so great to seeing all of you again!" The Digimon then tells you about the event that's about to take place: the deep-sea Digimon hold regular challenges to keep in shape, as it's hard to do so when everybody is swimming at great distances. This time Mantaraymon, the top swimmer they know, has hidden in a cave and all the contestants must find and win a battle against it!
Using the advantage of scanning the crags as you headed to the bottom of the ocean, your team immediately heads off to some caves. But after a while, only 2 return, the others having left to scout some other parts. Having a bad feeling, you arrive at the cave only to see your friends struggling to hold their position against the mighty Mantaraymon!
"I guess they didn't tell you about the power I possess. 5 Digimon against one is fine by me, this will be over in a short time!"