
Not only do Overnight charts have more notes and more complex rhythms, but they feature chords of three or more notes at once, whereas on Core you only ever have to press up to two notes at the same time. Most Overnight charts can be unlocked by clearing the song's corresponding Core chart with a B rank or playing it 5 times, with non-default, non-Asteroid songs additionally requiring spending Fuel to unlock. Unlike the other three difficulty levels, Overnight uses a 6×4 field. Harder Than Hard: Every song has a fourth difficulty level, Overnight.

That does not mean the charts are easier, however. All of its charts have notes that descend from above and land only on the bottom row of tiles, much like a more traditional vertical-scrolling rhythm game.

Prior to version 2.0, charts did not have difficulty ratings, but 2.0 adds a "Tier" difficulty rating system, with each of the four difficulties using its own scale: 1-2 for Enjoy and Handzup, and 1-4 for Core and Overnight, with each tier also having a "plus" sub-tier. Difficulty Levels: Each song has three or four: Enjoy, Handzup, Core, and sometimes Overnight.The Gameplay Grading uses stellar classifications for most letter ranks in order of lowest to highest, they are: U, M, K, G, F, A, B, O note however U is not actually a stellar classificaton and instead exists to serve as a failing grade.What other games call an "all Perfect" (all notes hit perfectly), this game calls a Super Nova. What other rhythm games call a "full combo" (no missed notes), this game calls a Nova.The unlock maps are named after constellations, galaxies, and other space objects: Station (as in a space station), Asteroids, Milky Way, Aries, Taurus, Gemini, and Cancer.Call a Hit Point a "Smeerp": Many elements of the game that are common to the rhythm game genre have unique space/astronomy-themed names:.You can obtain them by completing missions, or you can purchase Fuel Boosts with in-app purchases. Fuel Boost multiplies the amount of Fuel you get when playing a song.Instead, they can be used to immediately unlock Side Chapter songs, which normally cost S-Fuel.

However, as of 2.0, which abolished chips, Q-Chips are no longer used to specifically unlock Cores and Overnights. Before the 2.0 update, Q-Chips, which are a Premium Currency purchased with real money, could be used in place of regular Chips for unlocking Core and Overnight charts.Notes are colored an orangeish-yellow, except when they're simultaneous with other notes, in which case they are colored blue.The title screen features an orange-blue gradient.Tap notes are designed to look like bamboo shoots (one of the ingredients of a typical ramen bowl, while hold notes look like ramen noodles when being picked up by chopsticks.The starfield background is replaced with flying bowls of ramen.Note targets are redesigned to look like chopsticks.All of the song jackets are replaced with pictures of food, mainly ramen.
