Every time you beat Dr. Wily, not only you can get one of his parts, but also some contents will be unlocked in Versus and Time Attack Modes. You have to beat Dr. Wily with the same save file and racer one, two, three or four times in Grand Prix mode.
|Unlocked in Versus Mode and Time Attack Mode|
|1||Dr. Wily's car|
|2||Bass' Base course|
|3||Dr. Wily's Fortress course|
Duo & the Black Challengers
After you beat Dr. Wily, the Black Challengers will start appearing in Grand Prix mode. Tap a button (different recipes exist) while the starter lights are turning on, and a new challenger appear. They will appear usually in the same order, regardless of the courses you are in.
- Black Joe
- 5 Black Roaders
- Black Devil
- All of the above Black Troop at once
Every time you win one challenge, the defeated racer(s) will tell you a secret technique. Furthermore, an extra part will become available in a specific course. You have to collect the hidden question mark and win the race in order to obtain the extra part.
If you collect all four extra parts, Duo will become available in Versus and Time-Attack modes.
|N.||Black part||Challenger||Course||Question mark location|
|1||Blade tires||Black Joe||Quick Man's Ridge||Behind the jump.|
|2||Sky-High wing||4 Black Roaders||Napalm Man's Arms Factory||Behind the bottom tunnel divider.|
|3||Retro engine||Black Devil||Ice Man's South Pole||In a small niche near the end of the track; it's on the left, past a pit.|
|4||Hammer body||All Black Troop||Guts Man's Mountain||Where the track slopes down to the left near the start, hidden against the wall behind the slope.|
If your racer is one of the four in this table, the track where the part is hidden won't be available. Therefore, the part will be hidden in Shadow Man's Crystal course.
- Duo's Hard Grandeur and the car made of the four extra parts are different.
- The parts of Duo's car cannot be obtained in Grand Prix mode.
Two secrets were only available in the original Japanese version:
- If you win a Grand Prix circuit without losing any of the races, you will unlock a karaoke mode.
- If you beat four Grand Prix with the same character and save state (i.e. collect all Wily's parts) you'll see an alternate ending.