NiGHTS into Dreams is a game released by Sega in 1996 for the Sega Saturn system. It is the first game into the NiGHTS franchise.
The world of NiGHTS brings the dreams of humans to life. Two parts of the dream world, Nightopia and Nightmare, begin to clash when Wizeman begins to steal the dream energy from sleeping visitor. With his newfound power, he creates Nightmaren, nightmarish creatures which include NiGHTS and Reala. Seeing Wizeman's acts, NiGHTS defects and is imprisoned. Eventually, two children free NiGHTS and together they attempt to stop Wizemen and save Nightopia.
Nights into Dreams... is composed of seven dream worlds which are each divided into four "Mares".
Christmas NiGHTS is as Christmas-themed version of NiGHTS into Dreams... that contains only two stages, each a different version of Spring Valley for Claris and Elliot. The game was released in December 1996. In Japan, it was part of a Christmas Sega Saturn bundle. Elsewhere it was given away with the purchase of select Sega Saturn games.
The story of the game happens during Christmas, about half a year after Claris and Elliot met NiGHTS. Though they both enjoy the snowy Christmas season in the crowded city, they feel as if something is missing. Finding that the Christmas Star that usually sits at the top of the Twin Seeds Christmas tree is missing. At night, the pair sleep and head off to Nightopia, where was also Christmas. NiGHTS, noticing their wishes to find a star, assimilates them and soar Nightopa to find one.
Christmas NiGHTS uses the system's internal clock to change elements of the game according to the date and time. In November and January, the title screen label "NiGHTS: Limited Edition" is changed to "Winter NiGHTS", with the lush greenery of the environment being replaced by white snow. During December, "Christmas NiGHTS" mode is activated, resulting in further Christmas-themed alterations, such as item boxes becoming Christmas presents, Nightopians dressing in elf costumes, and Christmas trees replacing Ideya captures. The background music is replaced by an instrumental version of "Jingle Bells", as well as there being a "Christmas-like" rendition of the boss theme. During the "Winter NiGHTS" period, the weather in Spring Valley will change according to what hour it is. Other cosmetic changes are visible on New Year's Day and Halloween, and loading the game on April Fool's Day results in Reala replacing Nights as the playable character.
The disc features a number of unlockable bonuses such as character artwork. Further extra modes allow players to observe the status of the A-life system, experiment with the game's music mixer, time attack one Mare, or play the demo stage as Sega's mascot Sonic the Hedgehog. In the "Sonic the Hedgehog: Into Dreams" minigame, Sonic is only able to traverse the Spring Valley stage on foot, and the original game's Puffy boss is re-skinned as a "bouncy ball" version of Doctor Eggman. The music is a slightly remixed version of "Final Fever", the final boss battle music from the Japanese and European version of Sonic CD. The Christmas NiGHTS content is playable in the HD version of the original game after it is cleared once.