After a certain point in the story, you can return to Alvanista and challenge Mach Kid to another race. However, instead of the standard race theme, a rendition of the theme song from Ridge Racer will play. After clearing this rematch race twice, you will be awarded with the Special Flag from Rally-X, which can be used to revive a dead party member with full health.
Contributed by MehDeletingLater
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