The Sea Fox is a sleek miniature submarine with a blue and orange color scheme. It features a foreplane with a resilient and aquadynamic glass visor on the front and, two smaller engines on the sides of the back rear. It moves predominantly using screw propulsion via a propeller on its rear that strongly resembles Tails' twin-tails. It also has a flat nose for a headlight. The Sea Fox itself is equipped with lights for illuminating underwater caves and torpedoes that enable it to destroy obstacles.
In gameplay, the Sea Fox is deployed into yellow and blue water wells marked with the twin-tails symbol. While underwater, it can use a sonar to briefly display a mini-map on the lower screen of the Nintendo 3DS that shows the current undersea section with its points of interest highlighted, such as collectibles, obstacles, and the exist from the undersea section. It can also use torpedoes to clear out obstacles. However, the Sea Fox can only stay underwater for a short time before its energy gauge in the top right corner of the screen runs out, and taking damage from colliding with mines or undersea walls drains it faster. However, its time limit can be increased by collecting floating watches in the undersea sections. If the time runs out, the Sea Fox instantly returns to dry land.
Sonic Boom: Shattered Crystal
The Sea Fox first appeared in Sonic Boom: Shattered Crystal. In this game, its main purpose is to find hidden Blueprints in the underwater section. These underwater sections are rather simple in design, having completely black walls and a one-shaded background in a certain color that darkens as the player goes deeper. Each section has one collectible to find.
When using the Sea Fox's sonar in this game, a basic outline forming a mini-map of the current undersea section is shown on the lower screen of the Nintendo 3DS. Red triangles mark mines while green rhombuses mark the exit and collectibles.
In gameplay, the Sea Fox can be deployed by Tails into pipes inside the adventure levels by pressing . Once inside, the player enters a underwater section where they take control of the Sea Fox. While underwater, the player has to swim through the corridors and destroy mines and cracked walls with the Sea Fox's torpedoes. To fire the Sea Fox's torpedoes, press , and to use its sonar, tap the touchscreen on the Nintendo 3DS. Once inside a underwater section, the Sea Fox can manually exit it by entering a underwater pipe found within said section by pressing near it. Also, after obtaining the Blueprint, the Sea Fox must find the leave the undersea section through the exit pipe in order to get the Blueprint. If the time limit runs out before it exits the undersea section though, the Sea Fox will return to the surface and explode in Tails's face, dealing damage to him.
Outside the main gameplay, the twenty-eighth toy the player obtains will be a model of the Sea Fox
Sonic Boom: Fire & Ice
In Sonic Boom: Fire & Ice, the Sea Fox reprises its role from Sonic Boom: Shattered Crystal, where it is used to obtain hidden Trading Card(s) in underwater areas. This time around, the underwater sections have much richer environments, featuring cavern shadings, coral and undersea flora.
When using the Sea Fox's sonar in this game, a detailed outline of the current undersea section is shown on the lower screen of the Nintendo 3DS. Along with displaying red triangles that mark mines and green rhombuses that mark collectibles, the sonar also marks breakable obstacles as transparent frames and watches as purple dots.
In gameplay, the Sea Fox can be deployed into independent levels on the World Maps, meaning the player will directly enter a underwater section from a World Map. While underwater, the player has to swim through the corridors and destroy mines and environmental obstacles with the Sea Fox's torpedoes. To fire the Sea Fox's torpedoes, press , and to use its sonar, tap the touchscreen on the Nintendo 3DS. Once the Sea Fox obtains all Trading Cards in an undersea section, it automatically exits it. Also, clearing a Sea Fox level fast enough will award extra Ragnium.
|Darkened Depths||Sunken Caverns||Narrow Fathoms||Underground Tides||Aquatic Plunge||Deep Sea Dive|
|Ragnium||Clear level in 00:40 min||Clear level in 00:40 min||Clear level in 01:10 min||Clear level in 00:55 min||Clear level in 01:10 min||Clear level in 01:10 min|
- Like its main series counterpart, the Sea Fox is only used on handheld systems.
- Both games in which the original Sea Fox appeared in are playable on the Nintendo 3DS, the same system as the game this version appears in.