Can someone have more than one familiar?

Yes, but there is rarely a need or desire to. Few people regularly use enough magic consistently to need the services of a second familiar and establishing a second link is significantly harder since the spell needs to be altered to prevent interfering with the existing familiar link. The original familiar link itself also needs to be adjusted for similar reasons, but doing so is extra finicky because links are /really/ not designed to be fiddled with after creation.

What types of familiars are there? Also could a person be a familiar? And finally what types of magic does this world have?

Any animal can become a familiar, but the conditions of the link usually means aquatic ones aren't chosen. Familiars and masters can only be separated for a short time without becoming ill so an environmentally-limited creature poses major restrictions on the master. The separation sickness is why larger animals tend not to be used since they can create logistical issues when trying to travel ("no, sir, your horse cannot get on the plane"). The animal also has to be looked after and the volume of food they need doesn't change due to a link, though what they can safely eat would expand in most cases.

A human could be "made into" a familiar in the same sense that an animal can. The ritual does work on other people but keep in mind that the link is two-way, so the subject would be able to draw on the magic of the other person as well, which defeats the main point of a familiar in the first place. It is possible for another spellcaster to lend some power to another and otherwise participate in larger-scale spells without need for a familiar link. Other influences of the links like tether distance and the way it echoes senses can also become more complicated if both parties are human.

As for the last question, I'm afraid that's a bit of a broad one--can you be more specific?

Um, biomancy?

?

Magic used to change one's body or of another. It can also be used for healing.

Healing magic exists but is mostly used for things like flesh wounds and getting something to stop bleeding. The body tends to be very iffy when magic tries to do much below the surface, however. Curing an illness or repairing a broken bone, for example, tends to provoke autoimmune reactions. The reason this happens isn't well understood and there is ongoing research to find more safe and effective uses for healing magic.

It can be used to grow new limbs

That is one application being explored, yes.

How does one discover their magic?

Practice mostly. Magic requires drawing on aether and shaping it to one's design. The ability to do this improves with use and training like a muscle (for drawing on aether), but it also has an academic component (the shaping part). In other words, you can have situations where someone has the ability to draw on a lot of aether but no idea how to use it effectively or efficiently or you can have the opposite where someone knows a lot of theory and formula but lacks the ability to actually perform any of it. Flynn falls into the latter category due to his impairment, incidentally.

So someone could know this magic I speak of. Though their own trial and error

To a certain degree, yes.

Cool

I got here from your TSA e-mail and enjoyed reading all the stories. While reading it and thinking about it after I came up with a few questions which should help flesh out the setting.

Firstly I think it would be interesting to learn more about how a familiar is bound. Clearly after the binding the familiar gains sentience, and we know that they exist to help power a mage's spells. However we don't know anything about the selection of a familiar; do you have to befriend/tame it first, or can you go out in the wild to capture your preferred species? Is the species just a matter of personal preference? Do you get to choose the species at all? I could see a ritual that summons a wild animal that suits the personality of the mage instead of the mage going out to find a familiar.

This ties into my second question; how are mages trained and educated? Does the setting have a master/aprentice set up like training a journeyman craftsman in medevil times, or is it more big magic schools like Harry Potter? Going back to familiars, I can see the acquisition of one being a major moment in a mage's training, at least in traditional teaching methods for mages that don't rely on magicite for magical power. Is there some sort of ceremony or tradition to celebrate the achievement? Is it part of initiation as a student of magic, or is it later in training?

Thirdly, what are the strengths/weaknesses of magicite vs a familiar?

Finally, what kinds of magicite are there and how are they found/created? Are they all mined, or do you create magicite through magic?

Thanks for such good questions! I'll do my best to answer them.

1. The animal does not need to be tame, though having one that is docile or otherwise not being aggressive does help the process along. A familiar's species is largely a personal choice though some families and regions have traditions about which familiars are "proper".

2. Most magicians are taught by a relative until they get the basics down but what happens next can vary. Apprenticeships do exist but are more ad hoc arrangements rather than a formal system and get arranged often through connections and/or money, or if the child is extremely talented. Magicians are very competitive with each other and one is rarely willing to impart their secrets to another without strong reason. It is seen as a sign of prestige to have been able to receive the more intimate sort of training that an apprenticeship affords. Classroom settings are common but the mental picture should be more "rural school with one room" rather than Hogwarts, as far as size goes.

3. A familiar is actually normally obtained much later in life, usually around the 30's to 40's, and even then only if the magician actually finds themselves in need of one (not all do and some boast about not needing one). One thing I haven't done the best job of is emphasizing how unusual it is for Flynn to have a familiar at his age--his parents are both very talented and were able to bind one to him in an attempt to treat his own magical impediment. He's actually had Coby since he was about seven years old.

4. Magicite/magnetite (I am waffling on which term to use) is able to store magic with a higher level of efficiency than most inorganic materials meaning that instead of relying on an animal that you have to take care of, you could simply use a few fancy pieces of jewelry and the like. Unless you are in need of extremely large amounts of magic routinely, magicite is almost always the better option as far as efficiency goes. Part of Gears was supposed to involve the sort of transition from magic to technology, with the phasing out of familiars being part of that, though I'm unsure if this will necessarily be kept in its current form.

5. Magicite is mined and there is actually a large operation going on beneath Prevel. There is only one type of magicite ore, but it can be refined into different alloys like any other metal. Currently, my thinking on the stuff is leaning more towards "it's basically a fancy conductor", like iron/copper and electricity or something. One thing that is largely fixed is that magicite refinement is a relatively recent development, within the past decade or two.