The Sentinel Gate is the massive archway that stands at one side of Anvil. It is used by Imperial citizens to teleport to battle-grounds to fight the barbarians - as well as to go on quests throughout the Empire.
The Gate is an ancient magical device, it was constructed long before the time of the Empire. The Gate was discovered by the Urizen mages and presented by them as a gift to the Empire when their nation joined. The Gate was then moved to Anvil and erected there, where it has remained since.
The Gate allows the Empire to teleport people to critical locations in the Empire but only at a solstice or equinox. It is now a pivotal part of the Empire's military planning - the ability to strike against their enemies at critical locations has been so decisive that it influences the entire way the Imperial Military Council plan and conducts their wars.
The power of the stars creates connections between times and places - referred to by Imperial magicians as conjunctions. By using the Gate to access a conjunction a character can travel from Anvil to the site linked through the conjunction. The device is powerful and expensive, but not so powerful that it could not be replicated. However the Gate does not create conjunctions - it only provides the means to access them, so creating an additional Gate would not generate any additional conjunctions.
The Sentinel Gate at Anvil was bonded to the Empire centuries ago by Urizen magicians using a powerful Autumn ritual. Because of this, only Imperial citizens can use the Gate. Autumn magic can be used to create a link between the Empire and a barbarian or a foreigner to allow them to use the Gate - and Night magic can transform or disguise a target in such a way that they can pass through. In both cases, it requires that those using the Gate are accompanied by a greater number of Imperial citizens. In the opinion of Imperial magicians, the Gate is secure from intrusion - a belief supported by the last four centuries of use.
Partly as a result of this bond, the Gate can only be used to travel to places the Empire is connected to - either inside the Empire, on the borders or to locations where significant numbers of Imperial troops are present. In theory, the bond could be broken but it would then need bonding to a new nation or power to be usable at all.
Conjunctions only occur at a solstice or equinox but beyond this restriction they appear superficially to be random, defying attempts to explain or predict them using logic. Urizen magi use the Net of the Heavens to explain the clear serendipity in the conjunctions that arise that allows the Empire to intervene at critical moments - but this may simply be the natural hearth magic of the underlying constellations that links them to fate.
Any magician can detect the imminent presence of a conjunction by casting detect magic on the Gate. They can only detect the imminent presence of a specific conjunction in this matter - the caster must specify exactly what destination they are seeking to detect each time they cast the spell. If a conjunction for that location exists - then the spell will identify the approximate time and how powerful the conjunction is - expressed in terms of how many people can travel through the gate when the conjunction occurs.
Detect magic can only detect the imminent presence of a conjunction to a precisely specified location. It is not possible to use detect magic or rituals to detect all possible conjunctions for a wide area. Attempts to do this always fail. The spell is only as effective as the description of the location provided - ambiguous or unclear descriptions usually result in failure but may sometimes give erroneous answers.
Detecting conjunctions in this way is a form of prognostication, and is affected by the same limits that apply to all attempts to make forecasts or predictions using Day Magic. The information is always correct - but only at the specific time that the spell is cast - and only for the magician casting the spell. The information may change at any time and very occasionally different casters get different results. It is exceptionally rare for a conjunction to disappear once detected, it is slightly more common for new conjunctions to appear. Some Wintermark mystics claim this is because the conjunctions are linked to an individual's skein or perhaps the fate of a nation or even the whole Empire.
Operating the Gate
To access a conjunction to travel elsewhere in the Empire, the Gate must first be activated. The easiest way to do this is to perform the operate portal spell on the Gate - but any equivalent magic will work. Once opened the Gate remains open for a brief period, just long enough for those gathered to travel through it. After that, the outward gate closes and nothing further may pass through. It is impossible to access a single conjunction twice - the Gate can only be opened again if a second conjunction followed immediately after - an exceptionally rare event. Magic cannot restore access to a conjunction once the Gate has closed, no more than it can create new conjunctions.
Those who have made use of the conjunction to travel elsewhere in the Empire have a short period of time during which they return safely - usually around half an hour. The noted astrologer Aquila of the Glittered Towers compared it to the passage of the stars through the heavens. The conjunction begins when a specific heavenly body is directly over Anvil - only at the moment is outward travel to the destination possible. The travellers may return to Anvil at any time the conjunction endures, but as time passes, return becomes increasingly dangerous as the stars move out of alignment and the conjunction weakens. Citizens who have waiting too long to return have suffered magical backlash resulting in traumatic wounds and even death in exceptionally rare cases.
As a result, all Imperial magicians are taught a minor cantrip that usually allows them to calculate how long a conjunction they have used will last. Any magician that has used a conjunction to travel from Anvil can perform this cantrip without cost. It takes a few seconds to perform and if successful, lets them know approximately how long remains before they must return. The cantrip is not reliable, sometimes the influence of the stars is hard to detect and the spell fails.
Most conjunctions are small, they allow anywhere between ten to thirty people to travel, but there are usually at least two conjunctions at any time which are potentially much more powerful. A major conjunction occurs when several normal conjunctions occur at the same time - as a result they often present the option to choose a single destination from one of several possibilities. Imperial magicians soon discovered that these conjunctions could be accessed by the egregores to allow vastly more people to travel through - hundreds or even more - sufficient to achieve major military outcomes. Because of their potent military benefits, these major conjunctions are controlled by the Imperial Military Council which decides which nations will travel and how best to make use of the conjunction.
Even a major conjunction would normally only allow a few dozen travellers, but by drawing on the power of the egregore bond, the conjunction can be accessed by everyone bonded to that egregore. Stargazers who have studied the operation of the Gate and the formation of conjunctions claim that the bond produces a powerful hearth magic effect through the law of sympathy - a character using the conjunction is a single entity - but the egregore can use a major conjunction to allow their entire nation to travel through the Gate as a single entity.
To operate the Gate in this way, the egregore does not need to physically travel via the conjunction (although some choose to do so), but they do need to engage the egregore bond with those who are travelling. This is usually done using a small ceremony or simple arcane rite designed to epitomize the nation's spirit. Invoking the essential nature of their nation produces the required hearth magic that allows the nation to travel through the Gate - at a major conjunction - as if they were a single entity.
There are limits to the major conjunctions - which are only poorly understood by Imperial magicians - which restrict the nations that may travel together. These restrictions appear to be bound by the movement of the stars in some way - which nations may use the conjunction to fight together is rarely the same from one summit to another. While the restrictions cannot currently be predicted, they can be divined - using night magic. The civil service present the Military Council with a definitive breakdown of the available options for using the Gate's major conjunctions each summit.
Major conjunctions have other limitations as well. They vary in size, the smallest allows a single nation to travel while the largest allows four or five nations to travel. Using a major conjunction is enormously taxing for the egregore - an individual egregore is rarely able to make use of more than one or two major conjunctions in this way during an equinox or solstice.
Of course not... what a foolish notion! You have preordination all the wrong way round my friend.
Robert of Mitwold comes to Anvil because the power of the constellations compels him to; it arranges all matters so that our Marcher friend cannot help but come to Anvil and find someone who can assist him.The conjunction draws what it needs to it.
- The Gate can only be opened at predestined times. It is not possible for anyone or anything in the game to open the Gate at any other time.
- At the predestined moment, the Gate can be opened by any Imperial citizen. A magician can use the operate portal spell to activate the Gate, or an Egregore can do it using hearth magic.
- Any Imperial citizen can travel through the Gate when it is open. Foreigners and barbarians can only travel through the Gate using magic specifically designed to facilitate this - a ritual, item or eternal power, and only in the presence of an equal number of Imperial citizens.
- Magical creatures - beings that are created or summoned using magic cannot use the Gate.
- The Gate remains open for outward travel only for a short amount of time. No character or object may travel out through the Gate once the assembled citizens have passed through in good order.
- The Gate closes for return travel slowly. There is a set period of time for which return travel is safe, any citizen who delays too long may experience a magical traumatic wound when they eventually pass back through the portal.
- Any Imperial magician who passes through the gate can sense how long they can remain away from Anvil before the Gate closes if a referee is present. This ability requires a few seconds of appropriate arcane roleplaying.
- Characters can move anything through the gate that they can personally carry, including shared loads. Beasts of burden - and their loads cannot use the Gate.
- Sights and sounds perceivable through the portal can be perceived in-character.
- Sentinel Gate design - a longer explanation of some of the out-of-character design philosophy for the Gate.