Elfhome was born from the "Primordial Foam", a concentration of "raw existence" from which anything can be born. Interestingly enough, this Primordial Foam is exactly where Dkmak-Mab (later known as Queen Mab) was born, and thus she had a fundamental connection to this new quasi-plane. Of course, being fundamentally connected to the Embodiment of Chaos didn't do well for the plane. This new world constantly shifted and self-destructed, repairing itself all over again to start this new process. Chaos eventually decided to populate this plane, and from her very essence, she created twelve beings. These beings are now known as the nobles of faerie, and from them the rest of Elfhome was populated. The Fae were perfectly adapted to the chaotic landscape of Elfhome due to their status as being made from chaos, the only law that Elfhome seemed to consistently follow. The nobles of Faerie divided themselves into pairs, each claiming a sizeable amount of Elfhome and naming their "Court" after one of the four seasons, and the concepts that they were most connected to. Due to the Faerie Noble's fundamental connection with Elfhome, the environment itself shifted to match the noble's courts: Summer, Winter, Autumn, Spring.
And so...the reign of the seasons began, each court fighting each other for power under the delusion that there would be one season. The species and plane itself fluctuated as the fae changed, degenerated, and changed again -- nothing is constant in Faerie except for the Game. In modern times, Elfhome is warring against itself, with physical laws so chaotic and inconsistent that it's impossible to find any real order. The Eternal War is the war of the seasons to gain power, and the Game of Immortals is the "game" that faeries play in their lives, which replace any comprehensive physical laws entirely.
The Plane of Chaos: The Game of Immortals and other Physical Laws
The fae, especially Higher Faeries like Leanan Sidhe, Elves, and Nobles, have to follow a set of strange rules called the Game of Immortals. The Game is not only a code of behavior that all fae follow, but also the laws of their existence which they're absolutely unable to break. The Game of Immortals is possibly a result of Queen Mab forcing a contract upon the whole Faerie race, or it may be a set of rules they imposed on themselves; after all, all games need rules, right?
The rules of the Game of Immortals are as follows:
1) Never kill a mortal, unless in self-defense.
2) Never break an oath, promise, or contract. Always stay true to your word.
3) Never lie.
4) Always show hospitality to guests.
5) Always be remembered.
6) Never touch Cold Iron.
As masters of loopholes, the Fae have found numerous ways to break the Game of Immortals without truly breaking it (you cannot lie, but you CAN mislead; you must always show hospitality, but it never says what hospitality is). Due to the fact that the Fae are inherently delusional and alien-minded, this has led to a series of...strange actions such as stealing children in their sleep, destroying entire galaxies on a whim and re-creating them in a fit of sadness, and many other things. However, the price of directly (emphasis on directly) breaking the Game of Immortals is fading away from existence. Combine the Game of Immortals with the strange conditions that definitely come with making contracts with concepts, and the physical laws of Elfhome are definitely strange.
Into the Mind of Madness: The Psychology of the Faerie
Interestingly enough, due to the fifth rule of the Game of Immortals, stating a faerie always must stay remembered, a Faerie must be in constant conflict to even exist. Due to the Faerie's inherently being unable to make friends, in a strange way, a faerie's enemy is the closest thing he or she will ever have to a friend. The constant struggle to stay remembered and recognized leads to the belief in each and every faerie that they are special, chosen, and "holy" in a way.
A Changeling Tale: How Most Encounter Elfhome
For long-term stays, however, the Fae have an elaborate system. They stalk their prey for a while, getting a feel for their personality and essence. They somehow steal their shadows and weave it into small pieces of junk from the environment, allowing them to construct a perfect copy of the kidnapped. When the subject is kidnapped, the faerie replaces him or her with the copy, called a "Changeling", which will grow and mature as the original was supposed to, except he or she will always be "off". Changelings oftentimes don't know that they're changelings, and their artificial memories are a perfect copy of the original's memories. The parents, more often than not, never see the difference between the Changeling and the Fetch (the kidnapped). Now, the Fae don't always collect just children; adults and teenagers would do just fine if the Faerie wants a more challenging fetch.
As for the Fetch...they don't always escape. Sometimes they do, but it's not always easy to tell if you've escaped or not. If you have a more sadistic captor, the environment could easily be shifted to resemble your old home, and Changelings could easily be crafted to resemble your family and friends...
As for getting to Faerie, there are plenty of ways: mirrors, placing a phial of blood beneath a thorn bush, under certain beds...Elfhome collides with reality in various places too, creating weird amalgamations of both Elfhome and reality. In these areas, lesser Fae often roam with obscure goals.
The Fair Folk: The Eternal War and the Seasonal Domains
Most of the time, however, the Eternal War -- also called the Feud or the Legend -- has gone on and will continue to go on until the last universe ceases to exist. And possibly more after that. It is unknown what the courts have done to each other to start this Feud -- perhaps it was something petty, like a minor insult. However, each and every faerie noble remembers what happened, for it is not within the nature of the Fae to forget. And so they send soldiers to each other's kingdom to slaughter and be slaughtered for a cause they don't even know about, for the Fae will not tell anyone about it. But each noble participating in the Feud knows, and their eternal grudge burns with the same blazing flame that it has burned with since the beginning of time.
The Fae of Summerfell look exactly as you'd expect: athletic, warlike, battle scarred. They are locked in a permanent state of battle and rage, and it is in this state they thrive the most. The men of Summerfell are muscular and athletic, a true warrior image that harkens back to heroes of old. Their bodies are often painted with blood, and their bodies are scarred from many battles. The women of Summerfell are also tall and athletic, but their appearence reflects that of Summerfell: beautiful and deadly. They have the bodies of amazons, athletic and curvacious, deadly and beautiful. They often have tattoos carved into their flesh and skin red or orange as flame. They are passionate and, of course, easy to anger.
The Fae of Autumn are a little more varied than those in Summer. The male fae have a variety of eldritch forms fit to terrify all who look, and some are sleek, small, and undetectable, perfect for sneaking up and hunting. Some look perfectly normal, but there's just something off about them. It may be their behavior, it may be something strange about their appearance, but something about them just seems wrong. The female faeries are also varied, with some being old crones in the hedges, ready to eat any unlucky traveler that comes along. Some fae harken back to the enchantresses of old, deceptively beautiful while hiding an ugly soul.
The fae of Spring are generally attractive. Men appear to have traits deemed sexually attractive by whichever species looking at them, and women appear to have traits deemed sexually attractive by whichever species looking at them. It isn't all about physical attraction, though; the Spring Court seems to be amiable in comparison to how disturbing the other courts are. They seem to care about happiness and love...though this is eventually revealed to be a charade, and their ideas of "love" and "happiness" often lead to them being more deceptively twisted than the other courts.
The fae of winter generally look emeciated -- unaturally thin dwarves or starving warriors. The men of winter often look predatory and dangerous, sometimes taking on animal forms. Some reflect the sorrowful philosophy of Winter, with permanent blue tears running down their eyes or grimaces devoid of all home. Women of winter often look the same, taking on bestial and predatory forms, huntresses and torturers. Some of them are incredibly beautiful, so beautiful as to inspire love on sight. Some of them are meant to get close to a traveler...only to rip their heart out -- literally or figuratively. Winter is a cruel mistress, but its cold snow and bitter winds prepare one for what's coming next.
The Neutral Ground: The Bizarre Bazaar, Goblin Land, and other neutral territories
Not every domain in the land of Elfhome is locked in the Feud. In fact, it wouldn't be a stretch to say that most of Elfhome wasn't interested in the seasons' Eternal War, though this assumption is uncertain at best due to the fundamentally random nature of Elfhome. The soverign nations of Elfhome are apart from the seasonal domains, residing in the middle ground of Elfhome called Neutral Ground. From Neutral Ground, one can get to any of the seasonal domains; that is, if he or she is willing to brave the dangers in Neutral Ground alone. Neutral Ground itself is roughly estimated to be the size of Earth, and exploring the whole place is a tenuous goal at best. Luckily, Neutral Ground isn't just blank land:
The Bizarre Bazaar:
Each market in the Bizarre Bazaar has a set of rules that must be followed. The result of breaking any of these rules can be from simply getting kicked out, to beaten to death, to much worse. Sometimes it isn't even easy to follow the rules; sometimes they're obscure ones like you must always hop on one foot while speaking Mandarin. Sometimes they change at random, and you must keep constantly updated on the rules.
The Game of Immortals, part 2: The Great Struggle
Legend. What is a legend to a Gentry?
Legends, power, and status are the manifestation of existence to the Fae. Titles are equivalent to power to a Faerie, and killing another in the Eternal War is a way to get a title (and, by extension, more power). Names are important to Fae, and they often don't tell their true names to anyone, not even their supposed lovers. With more titles, a Faerie is more likely to not be forgotten, and thus making the Great Struggle easier. This fight for existence seems to be the primary drive behind the random behavior of the fae (well, that among other things).
When Chaos created faeries, they had eventually become separate from her, but part of her at the same time. It is an understatement to say that Elfhome and its denizens are anomalous compared to the rest of Vaggah li Akvak-Tomen, and there is a reason for that. The fact that they're able to follow different laws from the rest of creation except the aeons themselves is due to the Odd, a manifestation of the Quiet that somewhat acts as the overall "physics" that they follow. The Odd acts in a way very similar to Narrative Causality. When the fae are concerned, everything behaves in a way that's dramatically appropriate. That's why they're able to speak to concepts and inanimate objects where others are unable to.
Powerful fey creatures such as nobles and kings and queens can manipulate the Odd in a limited way, by fashioning an event or situation like a story they know of and allowing Narrative Causality to do the rest of the work for them. It is because of the Odd that the faeries act in whatever way they deem dramatically appropriate (what they see as "dramatically appropriate", however, is not gauranteed to be so from someone else's point of view). This further explains them thinking that reality is a game, because the Odd essentially enforces narrative causality on them, which changes the rules of reality for them to make it seem like a game in the first place.
An analysis of the Physics of Elfhome
Elfhome is, indeed, a strange place. Besides its inhabitants, its "rules" -- if it can even be called such -- are also very strange. Here is an analysis of how Elfhome works:
1) Elfhome exists in all ten dimensions and is present within every universe (keep in mind that the multiverse is infinite and has several variations of any given universe). At the same time, however, Elfhome isn't connected to any universe at all and exists independantly from all ten dimensions. Strangely, Elfhome also seems to have its own set of dimensions that exist independantly from the multiverse, with Elfhome proper always having a direction that leads "towards Summer, Winter, Spring, or Autumn".
2) After years of calculation and analysis, Archmagi have come to the conclusion that Elfhome isn't shaped like a bubble, but a klein bottle that goes in every possible direction in 10 dimensional space. This is made even weirder by the fact that, when measurements of the area of Elfhome are taken, it's completely flat and infinite in all directions, yet has no "center".
3) "Locations" in Elfhome aren't really located in any certain place in Elfhome; in other words, the Enchanted Forest, the Bizarre Bazaar, and the Seasonal Domains aren't in a point in Elfhome's space, but "towards" any one of the seasonal domains. For example, if you were in the Enchanted Forest and continued walking forward, you wouldn't reach the end of the forest no matter what, because there is no end, nor is there really a beginning, nor is there a space you were occupying that could be called your "point of origin". If you wanted to go to the Goblin Market, you'd have to "move" towards Autumn.
4) Stars and other celestial objects may seem to be upwards, but "up" is a dimension that doesn't accurately describe where (or rather "when") the stars are. Celestial objects are in fixed points in space-time, and from their perspective, all of Elfhome is stretched out evenly through all ten-dimensional space, revealing everything that has happened, will happened, is happening, and will never have happened, what isn't happening, and what will not happen in Elfhome.
5) Time is different inside of Elfhome as it is outside of Elfhome. In fact, it isn't a matter of "how long", but "had time agreed to allow you to ask, 'how long?'" Due to the contract law, time is wildly inconsistent and seems to change depending on what realm of Elfhome you're in. For this reason, many use Elfhome as a means of time travel, but due to the nature of Elfhome, it's inherently risky and random.