Complete One More Extra Stage; every Nonstop course; or the Paranoia Brothers Oni course.
Dance Dance Revolution
Play every song, then play about another twenty songs. You will then see it on your song list.
Dancer options
Play any course in Nonstop mode.
Darkness Oni course
Complete any song with the "dark" setting.
Emi (2) (4th) (dancer)
Complete fifteen songs with Emi (1) (4th) as a dancer.
Endless mode
Get 100 "A" or greater ranks (except in beginner mode)
From GF & DM Oni course
Receive an "A" or better on Mikenko Rock in Heavy mode.
From IIDX Oni course
Complete one Oni course.
IIDX Boss Oni course
Complete V (for EXTREME) challenge with an "A" or greater rank.
Keep On Liftin'
Pass every Nonstop course.
Legend Road Oni course
Pass True Demon Road Oni course.
Legendary Road Oni Course
Play every Max song. Max songs do not have to be beaten; just played.
Max Quartet Nonstop course:
Pass MAX. (period) as your EXTRA STAGE.
Naoki Premium
Complete the Naoki Neo-Standard Nonstop course.
Paranoia Survivor
Complete Paranoia Brothers Oni course. Alternately, complete any of the songs in the course under Heavy mode.
Paranoia Survivor MAX
Get an "AA" rank on every song in the Paranoia Bros. Max 2 Oni course. Note: Sometimes you might see it on your song list, but you cannot play it on challenge. You will only see it a few times.
PARANOIA Survivor Max
Get an "AA" or greater rank in all songs in the Paranoia Brothers course under Heavy mode.
Rap 5 Oni course:
Get an "A" or greater rank on Daikenkai challenge.
Rebellion of Oni (Oni course)
Master Light, Standard, or Heavy mode.
Remix Nonstop course
Complete the Standard Nonstop course.
RevenG and TaQ Oni course
Complete five Oni courses.
Reverse Oni course
Complete any song in Reverse mode.
Road of 2MB Oni course
Complete MAX. (period) as your extra stage.
Slow Road of Oni (Oni course)
Get an "A" or greater rank in bag heavy mode.
The Legend Of MAX
Pass The Legend Of MAX as your extra stage.
Tomorrow Perfume
Get an "AA" rank or greater.
Trip Machine survivor
Get an "A" or better rank on Trip Machine Survivor under Heavy mode as as semi-final stage.
True Demon Road Oni course
Complete 20 Oni courses.
Try 2 Luv. U
Get twenty "A" or greater ranks (except in beginner mode). Alternately, complete Lesson mode.
U1 (dancer)
Play MAX. (period) as player two.
Ultra 16 Oni course
Complete the Legend Road Oni course.
Un Deux Trois
Get fifty "A" or greater ranks (except in beginner mode).
Xenon
Get an "A" or greater rank on V (for Extreme) challenge.