Metal Sonic is the boss battle of Stardust Speedway in Sonic the Hedgehog CD. In this battle, Metal Sonic challenges Sonic the Hedgehog to a race. This boss battle is later returns in Sonic the Hedgehog 4: Episode II aboard the Death Egg mk.II Zone.
Sonic the Hedgehog CD
At the start of the race, the player will encounter Metal Sonic at a door, once the door opens, the race will start. The player runs through Stardust Speedway whilst trying to outrun Metal Sonic. If the player falls too far behind, the player will get hit by a high-powered laser fired from Dr. Robotnik's Egg Mobile, instantly losing a life even if the player has Rings. The race course contains many rises and dips as well as spikes, making it hard for the player to maintain speed. In addition, Metal Sonic has a couple of special abilities that can put him ahead, and attack, the player. If the player gains the lead, Metal Sonic can gain a burst of speed with the V. Maximum Overdrive Attack, allowing Metal Sonic to move ahead of the player and deal damages if hit by it. When in the lead, Metal Sonic will use the Ring Spark Field, causing Metal Sonic to emit electricity from his body at the cost of his speed. At the end of the race, there is a door not unlike the one at the start. If Metal Sonic wins the race, Metal Sonic will run through the door before it closes, causing the player to get hit by Robotnik's laser, losing a life whilst Metal Sonic gloats. If the player wins the race, Sonic will pass through the door before it closes, causing Metal Sonic to crash into the door and fall to his doom, forcing a disgruntled Robotnik to flee. Beyond the door, the player will find a tied-up Amy Rose, the player must free her in order to finish the boss level.
A re-imagining of this race appears in Sonic Generations, unlike the original encounter, the player fights Metal Sonic on a constantly disintegrating path as opposed to an actual race. Metal Sonic uses attack such as an Ring Spark Field, the V. Maximum Overdrive Attack, and snapping off streetlights to throw at Sonic. Unlike the original, which can fought in either the good or bad future (depending on the players choices), the battle is always fought in the bad future.
Meanwhile, the 3DS version of Sonic Generations is an actual race against Metal Sonic. However, the race takes place in Casino Night Zone (With the Stardust Speedway boss music).
Sonic the Hedgehog 4: Episode II
Metal Sonic once again challenges Sonic (along with Tails) to a race as the second sub-boss in Death Egg mk.II Zone Act 1. Unlike the original, the race is on much more even ground, however there are several sections where doors will fall down, obstructing the pathway, these doors can be destroyed with use of the Homing Attack with 3 hits, or the Rolling Combo with 1 hit (note that Super Sonic destroys the doors in one hit with any attack). Metal Sonic is also lacking the abilities he had in the original race, relying solely of his speed to outrun Sonic. As with the original race, the end contains a door (although this time it is electrified), if the player loses the race, Metal Sonic will run through the door before it closes, causing Sonic and Tails to crash into the door, losing the player a life. If the player wins, Sonic and Tails will run through the door before it closes, causing Metal Sonic to crash into it, defeated once again. It should be noted that if one uses the Rolling Combo or Super Sonic right from the start of the race, Metal Sonic is easily surpassed and any obstacles are instantly destroyed in one hit, thus one can use this trick to safely win the race if it proves difficult.
- This is the only boss in Sonic the Hedgehog 4: Episode II that has been reused from a previous game.