The Nonstop Challenge, also referred to as Oni Mode, is a feature new to DDRMAX2. It was officially renamed Challenge Mode in Dance Dance Revolution Extreme to avoid confusion with Nonstop Mode. The mode involves playing through 4-10 different usually themed songs with limited gaps between them just like in Nonstop Mode, but the traditional Dance Gauge is replaced by a "battery bar" with 3 lives (4 lives total,). A life is lost if a combo is broken (which is done by getting a step judged as a Good or less, or by breaking a Freeze). Lives can be regained after every song played, and some courses force different modifiers. If all lives (4) are lost, the game ends and the course fails. (The challenge Lives is also used at DDR Supernova 2 in Extra stage.)
In Challenge mode, the dance point system is slightly modified (Perfects and OKs are worth 2 points and Greats are worth 1, everything else is worth 0), and the final score is displayed as a percentage of the maximum possible dance points. The courses Naoki Standard, Nearly = 130, and Paranoia Brothers are used for rankings. Players are ranked first by how long they lasted, and then, in case of a tie, by percentage score.
Oni mode courses in DDRMAX2 sometimes have special song remixes that have a special difficulty, referred to as the Challenge difficulty and color-coded navy blue. The fan name of the mode comes from the Japanese name for the difficulty, 鬼 (oni, Japanese for demon). There are nineteen of these songs, and they are not available in the regular game mode in the arcade version of DDRMAX2. Some of these Challenge remixes do appear on Dance Dance Revolution Extreme as playable tracks.