The demo states that "[it] requires a 386 computer [and] runs perfectly on a 486/33 MHz [PC] with Tseng Labs SuperVGA". It supports various sound cards, such as the Sound Blaster, Sound Blaster Pro and, in a later version, the Gravis Ultrasound, which became the default choice for the demo.
The demo was made to run in standalone versions of DOS (up to 6.2), and will not run reliably under Windows 95 or later. However, it has been proven to run under the DOSBox emulator, albeit with an error in one part.
- Programming by Psi and Trug.
- Graphics by Pixel, Gore, Psi, Trug, Abyss and Dr. Venkman.
- Music by Skaven and Purple Motion.
Unreal was created for the first Assembly demo party, held in Kauniainen, Finland in July 1992. Because the organizers were unable to hook up a PC to their projector, it had to be shown on a TV screen. It won first place in the PC demo competition, defeating Overload by Hysteria. The demo was released to the public in August.
In December 1993, version 1.1 of the demo was released, which added Gravis Ultrasound support and fixed various bugs.
In January 2003, Unreal was captured to video for the MindCandy Volume 1: PC Demos DVD.
The demo is classified as a megademo, in that it consists of several parts, loaded separately, with different music for each part. The soundtrack, made by Skaven and Purple Motion in an early development version of Scream Tracker 3, was a mixture of styles, including orchestral, cinematic, new wave, and ambient pop (the "demomusic" style inspired by artists like Vangelis and Jean-Michel Jarre).
The demo contains the following parts (usually separated with a screen presenting the title of the following part):
- Introduction, with a starfield and a rotating Finnish flag.
- Two sets of scrollers, weaving over and under an image of columns. This part was shortened in version 1.1. (music: "The White Tiger" by Skaven)
- "Worldvector", a 3D animation scene with spaceships flying around a city on top of a cube in space. (music: Purple Motion)
- "Vectorballs", ball-shaped sprites (a.k.a. "bobs") morphing into various shapes. (music: "Lavender Hill" by Skaven)
- "Sinusbobs", coloured discs (which always face the screen) weaving in a Lissajous-pattern. The text "Apparently this is possible" blends over, testing the ability to fade in graphics on top of the vectorballs. In this part, more balls will appear on faster CPUs. (music: "Lavender Hill")
- "Wormhole", a funnel-shaped hole sucking its texture to the middle. The effect is accomplished with just palette rotation. (music: P.M.)
- "Shadebobs", a classic effect where rectangles additively blend over each other in various colors. (music: P.M.)
- "Colors", a showoff of a new video mode called "Mode X", which is essentially a "fake" High Color mode. The text first says "This is Real", accompanied by colored spots, then it changes into "This is Unreal" and the spots smoothen out into perfect gradient. (music: P.M.)
- "Realcolorplasma" is also a Mode X effect, where a Perlin noise plasma keeps colorcycling. (music: P.M.)
- "Realplasma" is the reiteration of the previous effect, only with sinusoidal plasma. (music: P.M.)
- "Something" shows a still handdrawn picture with first a scroller announcing the effect, which is a 3D vector-dot field on a complex Lissajous-like pattern, followed the 3D-animated letters "FC" flying across the screen. Like the "Apparently this is possible" part, more dots will appear with a faster CPU. (music: Skaven)
- "Texture" is one of the first texture mapping parts in a PC demo. It starts with a spinning cube, followed by pictures of FC members mapped on squares. The squares are distorted in different directions. This part is notorious for moving at wildly different speeds on different CPUs. (music: P.M.)
- "Landscape" showcases one of the popular attitudes in the demoscene at that time - showing an effect, then adding an extra twist to it. The effect starts with a simple scroller on the bottom, followed a rising landscape composed of vector dots, which eventually starts to scroll and revolve around the Y axis. (music: P.M.)
- Finally, the credits, a vertical scroller with the creators behind each part of the demo, as well as greetings. (music: "Realms of Chaos" by Skaven)
- First PC demo compo winner at Assembly.
- First demo to play 8 channel music, mixed realtime. (preceded by Fishtro by the same group, with the first demo soundtrack of more than four channels)
- First PC demo with a scene of multiple, independently moving 3D objects. Similar scenes had already been done in Amiga demos and PC games.
- First PC demo to use more than the standard 256 VGA colors by modifying the VGA color palette repeatedly within a single screen refresh.