The Bifrost Bridge, being a rainbow, requires mirrors and prisms to refract it further so it may serve as linkages beyond its original function. It is building (or stealing) these mirrors and prisons that the combined svartalvar/ljosalvar teams referred to as the "Asgard Corps of Engineers" are tasked with, and they're constantly looking for information on different materials or techniques to use in their refractory lens arrays. (The ljosalvar cover light-physics/metaphysics and testing, svartalvar the construction and repair.)
Of course, these child-bridges are reduced in energy over each refraction, so at some point the bridges will falter and become dangerously unusable. Some child-bridges may already be sending those who traverse them to the wrong destinations, or change them in strange ways, due to low-energy states or misalignment of refraction arrays.
The Bifrosts are not just a means of transportation. While traversing the rainbow bridge, those who keep an open mind can attune themselves to the various colors embedded in the spectrum. Attunement gives special powers or abilities. They work best while on Bifrost, but also have some effect off-bridge.
Novice traversers of the Bifrost attune to one color first. But everybody knows that the colors of the rainbow are not discrete and separate, but form a continuous spectrum. Experienced Bifrost-travelers can start attuning to colors up and down on the spectrum from the one they attuned to in the first place.
Red: Attuning to red is like putting one’s ear against a railroad track: the attuned creature can sense if there’s anybody else traversing Bifrost seven light years ahead or behind. Off-bridge, the attuned creature walks like a sailor getting off the ship for the first time in months: with a slight wobble; but this also makes them harder to hit with ranged attacks.
Orange: In this part of the Bifrost spectrum the trip becomes trippy! The Orange strain is a potent psychoactive resonance. Any creature that concentrates on Orange for a long time enters a trance state. It feels good. Takes your mind off the dreariness and boredom of the travel. But cannot wake up. Somebody else on the outside must wake them up. If somebody is attuned to Orange, they learn to wake up by themselves. The resonance can be captured between nano-particles, creating the so called "Orange Spice". In this form, the effect is sold off-bridge, as a drug.
Yellow: During the travel, the attuned creature does not need to eat food or drink liquid to sustain themselves. The vibrations of the yellow spectrum provide enough nutrition. The attuned creature can also go three day-night cycles without eating or drinking while exploring a location off the bridge.
Green: Green is the most malleable and corpuscular of all the colors in the Bifrost spectrum. An attuned creature can take a lump of Green and shape it into something useful and durable. A Green item is practically indestructible while on Bifrost, but deteriorates in three days if taken off the bridge. One creature can only take a limited amount of Green, but several attuned creatures working together can create bigger objects.
Blue: Located somewhere-but-not-quite-in-the-middle of the spectrum, Blue gives more or less balanced knowledge. Attuned creatures become better at navigating on Bifrost. Off the bridge, an attuned creature has a spell-like ability for three days. It's called "Define Direction": it's a locator spell for unstable environments. It doesn't give you an exact direction or location, but rather creates a stable point you can align your movement with. For example, if you are floating in non-Euclidean anti-gravity, you can "Define Direction" to stabilize yourself.
Indigo: A telepathic link is established between ALL creatures attuned to indigo. The communication channel remains functional even when off the bridge, but all thoughts are delayed, as they have to travel back to Bifrost first. Also, attuned creatures see everything through a distinct indigo-tint filter. It protects against bright flashing lights and lasers, but hinders perception as some minor details are blended into the background.
Violet: attuning yourself to violet let expand your imagination, the violet particles will coalesce around your daydreaming and take the shape of your fantasies. These constructs are not wholly solid and will appear like violet ghosts or holograms. They often become sentient and tend to act like muses. Like green items they can only exist for three days if taken off the bridge. But there is a song about a bard who crafter a prismatic to sustain a violet apparition that fell in love with her.
Infrared and Ultraviolet: mastering the red or the violet color can also let you peaks behind the curtain of the color spectrum and interact with the backstage of reality that touch the void…
\\\\VOID////: Most traversers of Bifrost think of it as a long corridor, enclosed by invisible walls on the sides. But in reality the rainbow is a spectrum, and its edges blend into the eternal cosmic blackness. There are no walls. After mastering red OR violet, AND one more color of the spectrum, one can risk attuning to the \\\\VOID//// that’s touching the edges of Bifrost. This is a deep, dark secret, and nobody knows (or nobody would tell) what happens when a creature is attuned to the \\\\VOID////.
1d6 Encounters & Events while traveling on Bifrost:
- Under Construction: This part of Bifrost got damaged, and is currently being repaired by a crew of Yellow Green Sevenarms. Their only goal is to patch up the holes in the rainbow and flatten all bumps on the surface. This includes the players.
- A hailstorm of frozen starlight. The shards are strong enough to penetrate standard armor and spaceship hulls. After the bombardment, the shards melt quickly – but if collected and then stored at absolute zero temperature, these star ice crystals can be used as prisms to refract Bifrost and put to other magical uses.
- The-Utterly-Alien-But-Maybe-Not-So Mind: The encountered entity is utterly mysterious, alien and unknowable. However, there is one little thing it shares with the players. Ask the players, what it is. Nothing spectacular, but still a chance to establish a connection with this entity. E.g.: similar music taste (it loves ‘Good Vibrations’ by the Beach Boys) or dislike for the name its 777 parents gave it.
- Indigo Knot: Contrary to popular belief, Bifrost is not a straight line: it’s full of curves, turns, bends… The Knot is a Moebius strip-like formation, where the indigo part of the rainbow spectrum is dominant. Traversing the whole length of the spiral takes infinity minus one second (but grants instant attunement to Indigo). With the help of the Indigo Dwarves it takes one second. But how can you get them to help you?
- Pam & The Prismatics!: The tour bus of the world-famous rock band broke down! And their mechanic is too high on Orange Spice to fix it. They travel with an elaborate light show (with tons of prisms, mirror and crystals) and powerful sound amplifying equipment, which they can lend to you if you help them out with the bus.
- This is a bad one: The Color from Out of Space! A parasitic chromatic entity, from outside Bifrost’s color spectrum. It shifts, shimmers, emits deadly cosmic radiation, drives everybody insane. How do you defeat a Color?