NiGHTS into Dreams... (or Nights into Dreams), is a video game released by Sega in 1996 for the Sega Saturn video game system. The game's story follows two children entering a dream world, where they are aided by a being called NiGHTS. NiGHTS into Dreams was developed by Sonic Team, with Yuji Naka as a producer and lead programmer, and Naoto Oshima as director and designer of the character. The developers' intention was to make the sensation of flight the central gameplay element, achieved through 3D graphics and a combination of both 2D and 3D gameplay.
Every night, all human dreams are played out in Nightopia and Nightmare, the two parts of the dream world. In Nightopia, distinct aspects of dreamers' personalities are represented by luminous colored spheres known as Ideya. However, the evil ruler of Nightmare, Wizeman the Wicked, is stealing this dream energy from sleeping visitors, in order to gather power to take control of Nightopia and eventually the real world. To achieve this, he creates numerous beings called Nightmaren, including two acrobatic jester-like, flight-capable beings called NiGHTS and Reala. However, NiGHTS rebels against Wizeman's plans and is punished by being imprisoned inside an Ideya Palace, a gazebo-like container for dreamers' Ideya.
One day, Elliot Edwards and Claris Sinclair, children from the city of Twin Seeds, go through failures. Elliot likes to play basketball but is challenged by kids from another grade and loses. Claris wants to sing in a play but is overcome by stage-fright in front of the judges. That night, the two of them arrive in the dreamworld and suffer nightmares about these incidents. They escape into Nightopia and find that they each possess the rare red Ideya of courage, the only type Wizeman cannot steal. They release NiGHTS, who tells them about dreams, and Wizeman and his plans, and the three begin a journey to stop Wizeman and restore peace to Nightopia.
NiGHTS into Dreams... is split into seven levels or "Dreams", each divided further into four "Mares" and a boss battle. The levels are distributed equally between the two child characters; three are unique to Claris, three to Elliot, and each play through an identical final seventh level, "Twin Seeds". Initially, only Claris' Spring Valley and Elliot's Splash Garden are available, and successful completion of one of these unlocks the next level in that child's path. Previously completed stages may be revisited to improve the player's high scores; a "C" grade in all the selected child's levels must be achieved to unlock the relevant Twin Seeds dream for that character.
At the start of each level, Wizeman's minions steal all the character's Ideya except the rare red type representing courage and take them to separate Ideya Captures. The goal of each of the four "Mares" in each level is to recover the stolen Ideya by collecting 20 Blue Chips and delivering them to the Ideya Capture, which will overload and release the orb it holds. It is possible to complete some of the levels' goals by wandering around the landscape of Nightopia as Claris or Elliot (pursued by an egg-shaped alarm clock which will end the level if it catches the player), but the majority of the gameplay centers on NiGHTS' flying sequences, triggered by walking into the Ideya palace near the start of each level and merging with the imprisoned acrobat.
In the NiGHTS sections, the player flies around a particular linear route through the Mare. The gameplay as NiGHTS is not completely 3D: players can only fly in the 2D plane of the screen, with their actual motion through the level determined by the automatic camera angle at that point in the Mare. The player has only a limited period available before NiGHTS falls to the ground and turns back into Claris or Elliot, and each collision with an enemy subtracts five seconds from the time remaining.
Various acrobatic maneuvers can be performed, including the "Paraloop", whereby flying around in a complete circle causes any items within the loop to be attracted towards NiGHTS. The game features a combo system known as "Linking" whereby actions such as collecting items and flying through rings are worth more points when performed in quick succession than they are individual.
After completing the four Mares, the player is transported to Nightmare to confront one of Wizeman's Nightmarens. The player has two minutes to defeat the boss, with the time taken contributing to the player's total score for that Dream. After each boss is defeated, a player can play a level again and choose via the menu which boss to fight.
Aside from the immediate game mission, the game also contains an artificial life ("A-Life") system, a precursor to the Chao featured in Sonic Team's later Sonic Adventure titles. The system involves entities called Nightopians (dream-dwellers, sometimes referred to as "pians"). The game keeps track of the moods of the Nightopians (harming them will displease them, for example), and the game features an evolving music engine, allowing tempo, pitch, and melody to alter depending on the state of Nightopians within the level. It is also possible to merge Nightopians with the small Nightmaren enemies, creating a hybrid being called a Mepian. It is even possible through extensive controlled breeding that a 'King' Pian or Superpian can be made. An expanded version of the A-life system was included in NiGHTS: Journey of Dreams.
NiGHTS into Dreams was introduced alongside an optional game controller, included with most copies of the game. This gamepad featured an analog stick, among the first on any game console (launching just after the release of the Nintendo 64, which featured an analog stick on its standard control peripheral). The stick, D-pad and shoulder triggers were located in an arrangement similar to that of Sega's later Dreamcast controller.
The PlayStation 2 port was released on February 21st, 2008 in Japan.
NiGHTS Into Dreams was released on the PlayStation 3 and XBOX 360 in HD October 2012.
The PC port is pretty much the same as the PlayStation 3 and XBOX 360 ports.
Voice Cast 
- Lynn Harris - Claris Sinclair (uncredited)
- Kazuyuki Hoshino - Elliot Edwards (uncredited)
- Jasmine Allen - Dreams Dreams (Kids Version) singer
- Cameron Earl Strother - Dreams Dreams (Kids Version) singer
- Curtis King Jr. - Dreams Dreams (Adult Version) singer
- Dana Calitri - Dreams Dreams (Adult Version) singer
Other characters were voiced by various anonymous Sonic Team members.
The following list is about the achievements that can be obtained in the HD remasters. It takes around 6-8 hours to unlock all of them. 
|The IDEAL||Clear Spring Valley in either BRAND NEW DREAMS or SEGA SATURN DREAMS.||10|
|The POSSIBILITY||Clear Mystic Forest in either BRAND NEW DREAMS or SEGA SATURN DREAMS.||20|
|The CONFUSION||Clear Soft Museum in either BRAND NEW DREAMS or SEGA SATURN DREAMS.||30|
|The AFFECTION||Clear Splash Garden in either BRAND NEW DREAMS or SEGA SATURN DREAMS.||10|
|The CONSCIOUSNESS||Clear Frozen Bell in either BRAND NEW DREAMS or SEGA SATURN DREAMS.||20|
|The REVIVAL||Clear Stick Canyon in either BRAND NEW DREAMS or SEGA SATURN DREAMS.||30|
|The GROWTH||Clear Twin Seeds in either BRAND NEW DREAMS or SEGA SATURN DREAMS.||40|
|Into dreams...||Clear all stages with a score of Rank A.||50|
|DREAMY !!!||Show your supreme skill by achieving the highest Acrobat Time rating, "DREAMY".||30|
|Paraloop Master||Try to Paraloop all of Gillwing’s tail in one hit. ||100|
|Mystic Garage||Try to guide the lost car in the Mystic Forest to the garage. ||10|
|Hello Mepian||Make a Nightopian and a Nightmaren have a hybrid offspring. ||40|
|Merry Christmas!||Clear Spring Valley (Christmas).||10|
- In the anime Durarara!!, there is a scene where Celty and Shinra appear playing video games in the episode "Declaration of Dissolution" and it is possible to notice that NiGHTS into Dreams is among the games.
- During an Interview, Yuji Naka revealed that Steven Spielberg, a famous movie director known for movies such as Jaws, E.T. the Extra Terrestrial, Schindler’s list, Jurassic Park and Ready Player One and also one of the co-founders of the Dreamworks Studios, visited SEGA during the development of NiGHTS into Dreams and he was the first person outside of the SEGA team to play the game. He was also the first person to play with the new controller, which since then, became known as the Spielberg Controller. 
- Coincidently or not, Elliot shares his name with the human protagonist from E.T. the Extra Terrestrial.
- The game has a score board with names of characters from the Sonic the Hedgehog series. By hacking the game files, it's possible to find an unused score board with names of characters from the Virtua Fighter series. 
- The track "Know thyself!", which was unused in all versions of the game, can be found in the PC port, but not in the PSN or XBOX Live Arcade releases.
- A mysterious easter egg can be randomly found after defeating Puffy. There are two big green doors at the end of the hallway that may randomly open after the battle. If they do, it's gonna be revealed that there's a lamp-post like object inside of it. The object either falls out or it will just stand still. The reason why this happens or the meaning of it is unknown. 
- The object appears to have "face" in it, however it's hard to see it, as when the object is inside the closet, the object is with it's possible face turned to inside the closet and when it falls, it will turn it's face to a direction which the player's view can't reach.
- The development team created a fictional language called "Dream Language" for the game which is spoken by the Night Dimension residents. Before the Reala's battle, he will say "Beadichinoa NiGHTS", which means "Let's go NiGHTS!" and when NiGHTS unfuses with either Elliot or Claris, he will say "Adeema", which means "Good-bye" in dream language. 
- Many people believe that Reala actually says "There is no NiGHTS!" before his battle. But Yuji Naka already disproved it.
- To celebrate the game's 15th anniversary, OverClocked ReMix (OC Remix), a community which makes video game music with composers from all over the world, made a fan album for NiGHTS into Dreams, called NiGHTS Lucid Dreaming. 
- Yuji Naka and Takashi Iizuka themselves were gifted with a copy of the discs.
- Shigeru Miyamoto, the creator of Mario, Donkey Kong and The Legend of Zelda revealed himself to be a fan of the NiGHTS series. In an interview back in the Dreamcast times, Yuji Naka once said that many fans including Miyamoto himself were curious to know if a new NiGHTS game was in development for the system. 
- Additionally, there's also a famous Miyamoto quote known among the NiGHTS community, where he says "If there is a game I would have loved to work on, it would be Nights into Dreams…” 
- In the HD remaster, the letter "B" in the ranking roulette is upside down.
- Every major character, boss and minion as well as all of the levels from this game appeared in Sonic Pinball Party.
- Nights into Dreams... at Wikipedia
- Sega Saturn version official site (archive)
- PlayStation 2 version official page (archive)
- PlayStation 3 and Xbox 360 versions official page
- NiGHTS into Dreams... in Steam
- NiGHTS into Dreams Manual (PDF)