Submarine Combo

The Submarine Combo is a Tag Action in Sonic the Hedgehog 4: Episode II which allows Tails to carry Sonic underwater, like a submarine. This move is unlocked in Sylvania Castle Zone, Act 2.

Unlike its counterpart, the Copter Combo, the Submarine Combo has no actual limit, allowing Sonic and Tails to swim through the water until they exit the move by pressing the Tag Action button again, or get out of the water. However, Sonic and Tails can still drown, and the two are vulnerable to damage from Badniks and hazards.

Trivia

 * Using the Submarine Combo Tag Action, or any other Tag Action, while you are Super Sonic will revert Sonic back to normal.