The Sea Fox is a customised submarine built by Rotor Walrus for Miles "Tails" Prower in 3235, as Tails had wanted a submarine ever since Rotor finished his Bathysphere submarine. While Rotor did build the Sea Fox for Tails, Tails wasn't allowed to use it properly per Princess Sally's orders as she thought him too young, and made sure Rotor didn't put any oil in the Sea Fox and would just let Tails play in it. But thanks to an oil-soaked seagull in need of assistance, Tails was able to make the Sea Fox operational and kept everyone in the dark about it. Tails used the Sea Fox to destroy Dr. Ivo Robotnik's new underwater robot factory and henchmen Octobot, to go out to sea and meet a fake Fiona Fox on an uncharted island, and to investigate a list of items left behind by Robotnik for his Sub-Boss, Crocbot. The Sea Fox would continue to be Tails's main means of oceanic transportation until its destruction during Operation: EndGame. It was later recreated and used by Tails to bring Antoine and Bunnie D'Coolette to Cocoa Island for a vacation.
The Sea Fox was built in 3235 by Rotor as a gift for Tails who wanted one for a while. While Rotor did build the Sea Fox for Tails, Tails wasn't allowed to use it properly on Sally's orders as she thought him too young. To that end, Rotor didn't put any oil in the Sea Fox so Tails could only play in it. Tails was enraged by this, but heard clapping and saw an oil-soaked seagull in the water of the dock where the Sea Fox was tied up. The seagull revealed that he had swam all the way to shore and that Dr. Robotnik had rebuilt his sub-merged, waterproof robot maker that the Freedom Fighters had destroyed. The seagull pleaded that Tails go after it and Robotnik's new Sub-Boss stationed there, so Tails used the oil the seagull was covered in to make the Sea Fox operational, and went off on his mission. Tails quickly made his way to Robotnik's new sub-merged, waterproof Roboticizer and spotted Robotnik's new henchmen, Octobot, guarding the entrance and capturing sea creatures to be roboticized. Tails attacked Octobot using the drill on the Sea Fox, causing the Octopus robot to release the sea creatures. Tails then launched a torpedo at the robot maker that caused a massive explosion, propelling the Sea Fox and Octobot to the surface of the ocean. Tails then returned home and left Octobot in the ocean, who vowed to one day return. (OSM: #1, STT)
Get Away Trip
After Sonic slapped him around while under Robotnik's control, Tails stormed off in his Sea Fox for being treated like a kid all the time. Tails's departure was noticed by Robotnik, however, via a secret camera hidden in a tree near the dock. Robotnik decided to use a leftover Auto Automaton from his recent skirmish with Princess Sally to try and trap Tails. Meanwhile, Tails came across an uncharted island and heard a cry of "HELP!" and saw a female fox in trouble. Tails flew out of his Sea Fox and fell in love the moment he laid eyes on what was actually the robotic replica of a younger Fiona Fox. Tails then spent a romantic day together with Auto-Fiona, and Robotnik soon had Fiona lure Tails into a hidden Roboticizer, but he escaped by clogging the machine with fur from his tails. Tails was then attacked by the Auto Automaton Fiona, but she fell into the water surrounding the island and rusted, paralyzing her. After taking the robot Fiona out of the water and placing her on the island as a monument, Tails then began to clean up the litter Robotnik left behind, and came across a list of supplies that confirmed that Robotnik had plans for a satellite operation somewhere on the planet. At first, Tails thought he should call Sally and tell her about it, but then believed that the other Freedom Fighters would leave him behind again if he did. Tails then decided to prove himself by going on this mission alone and returned home to Knothole in the Sea Fox. (StH: #28, #29, PSM: #1, #2, #3)
Second Mission and Attempted Scuttling
Tails used the Sea Fox later to investigate the supply list he had gotten off of Robotnik. Deciding to keep it a secret and go his mission solo, Tails took the Sea Fox out into the Mobian Ocean and spotted a blimp filled with supplies that was using an "umbrella cloak," stopping anyone from seeing it unless they were directly underneath the blimp. Tails flew toward the blimp to and saw they were heading to Downunda, but a flying Swatbot blasted him with a disruptor, causing Tails to fall toward the ocean with the Swatbot in pursuit ready to destroy Tails. Tails managed to recover in the nick of time, however, and did away with his pursuers. Tails went back to the Sea Fox to think up a new plan, but Octobot was lying in wait for him and captured him. Octobot then used his tentacles to punch holes in the the Sea Fox, causing it to sink, and then dragged Tails underwater. Thankfully, the Plankton Intelligence Agency alerted the Forty Fathom Freedom Fighters of Octobot's doings and saved Tails before he could drown, but the Sea Fox had been left scuttled. It was not he end of the submarine however, as the Forty Fathom Freedom Fighters then went back to the area it went down and Ray's friend, Brain Coral, repaired the Sea Fox for Tails to use to return home once he completed his mission in Downunda. (StH: #28, #29, TMS: #1, #3)
After Knuckles vowed to find the Sword of Acorns in an attempt to return King Acorn to normal, Tails took him to Downunda to find Athair. Believing the echidna wiseman to be Knuckles's best bet to locate the artifact, Tails had a suspended side-seat installed to allow a second passenger, which Knuckles didn't especially enjoy. After finding Athair's mystical connections were legitimate and getting his first clue, Knuckles departed on his quest while Tails returned home in the Sea Fox. (StH: #42)
Southwest as the Flicky Flies
The Sea Fox saw its next excursion when Sonic, Tails and Rotor were assigned to investigate a communication from Robotnik to Robotropolis which was triangulated to have originated on a small landmass in the southwestern Mobian Ocean called Flicky Island. Once there, Tails flew from the Sea Fox for aerial reconnaissance, only to be attacked by a flock of roboticized Flickies and fall into the sea. The sea water was revealed to restore the Flickies to their flesh and blood state and Sonic went on ahead to confront Robotnik while Tails and Rotor established a beach head on the island, spraying the Flickiebots with water blasters, and destroyed the roboticizer. (SBS)
Destruction and Recreation
After Dr. Robotnik launched Operation: EndGame into action and took the citizens of Knothole prisoner, Rotor and Tails temporarily escaped and made their way to the secret underground canal system where the Bathyshphere and Sea Fox were housed. They hoped to get away and make contact with any other Freedom Fighter groups that might be able to help them, only to be caught by Drago Wolf and a horde of Combots who had destroyed the undersea vessels. (StH: #47, #48, #49, #50, SSS: #6)
Two years later, after the defeat of the Iron Dominion, Antoine and Bunnie D'Coolette went to Cocoa Island with Tails on the Sea Fox to have a honeymoon and a break from fighting. The Sea Fox was upgraded with two smaller seats which, while not exactly roomy, were a step up from that used by Knuckles in the past. Their submarine's approach did not go unnoticed though, as some unseen watchers observed them beaching on Cocoa Island's shoreline through a hidden periscope camera from a third sister island that Tails had never seen before. That evening, a contingent of troops from the Battle Bird Armada attacked the vacationers and cut them off from the Sea Fox, leading to Bunnie and Antoine's capture. Due to Tails' escape, an armed guard was set up around the Sea Fox the following day, however they were easily neutralized and Tails set out in his sub with T-Pup to rescue his friends. Deducing the third island to actually be the enemy's base, Tails began to look for a way in, but was ambushed by a group a min-subs that could not be detected on the Sea Fox's sensors. Dispatching them easily with its laser array, the Sea Fox did take some torpedo damage in the ensuing battle and was forced to surface. This resulted in the Sea Fox saving Antoine when he landed inside it on top of Tails. After a quick discussion, the three of them used the Sea Fox's drill to cut away some of the land and moored it in a makeshift cove. They then left the submarine in the water to look for an entrance to the armada's island fortress. (SU: #17, #18, #19)
- The Sea Fox submarine was originally introduced in the game Sonic Triple Trouble, and made its final appearance in Tails's own game, Tails Adventures.