Prayer & The Gods

A prayer is... Well it's hard for us as mortals to describe. The few scholars who've been blessed with the opportunity to speak with The Eternal Emperor on matters of metaphysics and divinity have asked him about prayer and his answers have been amazingly forthright. He has described a prayer as a voice that he can hear in his mind, or even a notificiation provided to him by the system and says that there are three kinds of prayer.
Undirected prayers which are desperate appeals to the universe itself for intercession, and are the hardest for him to hear, are one kind. Another kind are direct appeals to him, requests or even, if one is foolish and angry, demands of him. The final kind of prayer is another kind that is made directly to him, but does not involve requests.
These are the kind he says he likes the most. These last kinds of prayers are conscious efforts by his worshippers to send him messages, often detailing their days and letting him of their activities, there is no ulterior motive behind them they are simply an effort to speak to their emperor and god. When asked why he liked those messages, he did not elaborate. Instead he merely smiled at the scholars who asked him that question. Not many people know that The Eternal Emperor has... a bit of a sense of humor. 

-On The Nature of Divinity, the first treatise on the subject of gods written by mortal sages and edited by scholars who live in the Althonite Empire.

Higher beings are incredibly powerful entities with powers that are capable of rewriting reality. Even the weakest sort of higher being can hear appeals to the universe and appeals directed to them by lesser beings, across vast, interdimensional distances. Both higher beings and lesser beings refer to these appeals as prayers, though that is not a fully fair thing to call prayer. 
Prayers need not be requests or appeals for intercession, and many good-aligned higher beings and higher beings of knowledge knew this and taught that to their followers. Knowledge of prayer was once so commonplace that prayers continued to be practiced by various civilizations and empires that the practice persisted even into the Althonian age. 
Deities gain the ability to hear prayers, both ones directed towards them and undirected ones uttered towards the universe, whenever they unlock their powers over the domain of faith. The faith domain is one of the innate domains that all deities possess power over from birth. Other higher beings can hear prayers, both ones directed at them specifically, and undirected ones, from either birth or whenever they become higher beings.
Author's Note: This is a living article, on a living wiki. It is entirely possible that new content will be added to this entry at a later date and as such please consider this article to be one to check in on from time to time if you like the story.

Manifestation

Barring an immediate, supernatural response, it is often difficult to tell if a prayer has been successfully sent out. Supplicants making prayers, especially ones that are fervent requests or appeals for aid, are taught, quickly, not to expect immediate or flashy answers.
That said, all higher beings can hear undirected prayers and the system corrects prayers that are sent by lesser beings with strong, clear mental visuals of the deity but a minor mistake like the wrong name, barring some unusual intervention like a powerful deity of lies and trickery deceiving worshipers, is corrected by the system. The system errs on the side of caution when it comes to prayer and opts to try and help beings who pray connect with beings who can answer prayers. 
In the wake of beginning his empire, Althos himself pretty frequently answers prayers in the forms of blessings, magical aid such as healing, or in exceptionally rare cases, some form of direct manifestation or other supernatural intervention such as robots or golems appearing to perform some task. Those instances in which he directly manifests and answers a prayer are usually reserved for the most desperate of situations, and there is almost always a cost to be paid by those who decide, boldly, to make those sorts of prayers. In some cases, the cost will be paid much further down the road, even years later, but Althos only rarely manifests directly to answer a prayer and doesn't exact some sort of payment.

Localization

This is what's known as a multiversal law, which means that it, in some form or another, transcends universal boundaries. That said, the system itself doesn't exist in every universe and so there are areas in existence where prayers are much more natural and unaided by a metaphysical means to course-correct for lack of a better term, prayers that are intended to be heard but are misdirected.

Type

Metaphysical, Divine