A small, clear orb that can be easily held in one hand, though one could not close their hand around it. About 1lb in weight, glass in appearance, and pleasantly cool to the touch. There is a small, ornate “L” engraved onto its surface.
Lytharian, Sorcerer of Light, was considered to be the foremost expert on Luminology in his age. If you have ever come across a spell that required the “light of a harvest moon” or “starlight from a midsummer's eve”, it is almost certain that the spell can be traced back to Lytharian and his research. The wizard devoted his life to the properties and composition of various light sources and their use in magic.
Of course, accurately cataloging the effects of a light source was both tedious and vastly time consuming. Ordinary moonlight and starlight were bad enough, requiring the old wizard to freeze his bones in the cold hours of the night to conduct his experiments. But rarer light was almost impossible to study, with the proper conditions coming as infrequently as they did. I would like to see how many times you could perform a lengthy ritual under the “midwinter sun in the year of the lamb” without botching it due to time constraints, hunger or other human error. And then to wait another year or two or ten to repeat the process and validate your data!
Frustrated by his slow progress in this area, Lytharian sought for a means to capture and store these light sources for later use. He spent several years closeted in his laboratory, studying lux mites and other magical fauna and flora to unlock the secrets of light absorption, amplification, and storage. Finally, after much trial and error, Lytharian emerged with what some consider to be his greatest work: the Luminescent Orbs.
Though he later created several orbs with various refinements, most of Lytharian's orbs are of the basic model: hand-held, easily portable, with good (but not unlimited) storage capacity. It is believed that he created several hundred of these for his own use, and perhaps a dozen more as gifts to various friends & dignitaries. Unfortunately, the secret of their making was lost with Lytharian's death.
Can absorb, store, concentrate and discharge various light sources. Moonlight, starlight, sunlight, torchlight – all will be preserved faithfully within the orb. Light emitted from the orb at a later time will have all the same properties & effects as light from the original source; therefore letters that can only be read by “starlight at the autumn equinox” (for example) can be read by the light of the orb, as long as the proper light has been stored in advance.
Light can be stored indefinitely within the orb without fading, though storing a new light source will destroy the old one. It is also worth noting that the orb is strictly luminous -- that is, it will give off light without heat. Thus it will always remain cool to the touch.
Use and Activation:
An orb can be commanded to start/stop absorbing, and to start/stop emitting light. With some study, the players may discover that the orb can also be commanded to increase or decrease the intensity of the light output. Also, the orb in question must be touched by the user when the command word is spoken (this was to avoid confusion between several orbs in Lytharian's laboratory).
An orb's storage capacity is 8 hours of bright light. To charge it up to capacity will require 8 hours of bright light, 16 hours of dim light, etc. The radius of the orb's illumination will depend on the concentration & type of light that it is emitting. For example, torchlight will have a smaller radius than sunlight, unless concentrated to a greater brightness .
Can be used to "purify" light: when the orb absorbs sunlight filtered through the trees for 4 hours, for example, it is still storing sunlight. When asked to release this light, the orb will by default release the sunlight in its original dilution (i.e. same brightness as under the trees). However, because the orb can be commanded to increase its output, it can discharge more of its stored sunlight at once -- to the consistency of a sunny day, for example. Note that this will decrease the duration of light output (1-2 hours, instead of the original 4).
When absorbing light, the orb will cause a noticeable darkening effect. If absorbing light from a large source, light the sun, it will be seen as a slight shadow/haze in the general area (10 yard radius). If absorbing a small light source, it may be enough to cause total darkness. Absorbing the light from a single candle, for example, could plunge the room into pitch blackness, though the candle is still burning! That means that the candle will still be hot (capable of burning a finger!) but won't be seen.
After Lytharian's death, these orbs found their way into the hands of individuals who discovered very different uses for the orbs' power:
Mages of all dispositions have used the orbs as storage for light components (naturally).
Adventuring parties have found them to be invaluable light sources.
Thieves and others have used them to quickly darken a room.
Stored sunlight has been used as a weapon against vampires and other undead.
Stored moonlight may have been used to force a werewolf transformation (if you believe the rumors that werewolves require the light of a full moon to transform).
Those who keep exotic light-feeding pets (like lux mites) have used them as a food source.
Medics have used these to bring sunlight to patients trapped indoors.
Some light-fearing magical creatures have used these to completely darken a dungeon room, as the dim ambient light will be constantly absorbed by the orb and destroyed when it has reached maximum capacity.
A note of caution: it is entirely possible to capture small creatures within these orbs, as long as they are composed of pure light. This can be very dangerous, depending on the strength and intelligence of the captured being – the more intelligent will be driven insane with long storage, while nearly all will have a nasty disposition when released, at the very least. Lytharian once unintentionally absorbed a small swarm of will o' wisps while collecting moonlight, to near disastrous consequences when he brought those orbs back to his laboratory. From then on he always assigned an apprentice to watch the orbs when they were set out to collect, to shoo any wandering lifeforms away. The use of these orbs against larger light elementals is unstudied, and is strongly discouraged.