ScatheAriiasqDrayceon
Just cause I read worse don't mean it ain't cursed
~Phoenixes~
As you have likely gleaned from the premise, phoenixes are born from the combination of a rare mutation and an "activation". Knowledge of the activation isn't common (although most phoenix hunters and active phoenixes know of this). In order to activate phoenix wings, you must set your wings on fire (which is dangerous for obvious reasons). Activation comes with a physical change in the wings (they become particularly shiny, have a slight glow, and turn red, orange, yellow, or a combination of those colors), and access to the abilities associated with a phoenix.
Phoenix abilities vary between individuals, but the one they all share is rebirth. If a phoenix is killed, then they will revive within a day and revert back to the state they were in when they were activated with their memories intact. This usually leaves them weak and tired for around a week afterward, but it this can go on for a month depending on how much energy it took to reverse their death. The only way to permanently kill a phoenix is to remove it's wings, otherwise prevent them from using the magical energy within them, or make them use up all of their magical energy without giving them time to replenish it.
Phoenixes may also have secondary abilities, such as fire resistance, fire manipulation, or healing tears. These vary greatly, but they all are at least somewhat linked to what abilities we would imagine a phoenix having (fire related, healing related, etc). Keep in mind that they already have self-revival, so try not to go too overboard with these.
The phoenix mutation is not limited to bird-based wings. Anyone could have the phoenix gene and no one (themselves included) would be any the wiser. However, pre-activation phoenixes tend to have no secondary abilities related to their wings (regular secondary abilities explained under "Wings"), and -if they do have them- then they will lose them upon activation in exchange for their new abilities.
Parts of phoenix wings (feathers, scales, wing dust, etc) can be used to power strong spells due to the large amount of magical energy within them. However, phoenixes cannot use these components for themselves. This is because these magical energies are already harnessed to them for the purposes of sustaining their life-force and/or powering their secondary abilities. Even an unrelated phoenix trying to use a phoenix-based component cannot, because the component is naturally predisposed to sustaining the life-force/powering the secondary abilities of phoenixes.
~Wings~
Secondary abilities are not limited to phoenixes. Wings come in all shapes and sizes, and oftentimes come with abilities secondary to flight. A person with dragon-based wings might be able to breathe fire, for example. Some bird-based wings may come with air current manipulation. These abilities may be similar to spellcasting, but -while they technically may be powered by magical energy- they are not considered spells. They're just something that some people can innately do. Not everyone has secondary abilities, but they're fairly common (it's about a 50/50 split).
Some wings also come with secondary physical traits, such as claws, patches of feathers, or sharper teeth. These traits are almost always somewhat minor, and never alter a person to the point that they are unrecognizable as human. For example, a person with dragon-based wings may have sharper teeth, but they won't have an entire dragon head. A person with bird-based wings might have eyes similar to an owl's, but they won't have a beak.
Wings are genetically inheritable. Excepting odd mutations, a child will have wings of a similar type to their parents. Two people, one with falcon-based and one with hummingbird-based wings, may have a child with seagull-based wings, or various other types of bird, but they will likely not have a child with insect-based wings.
~Magic~
Magic as we imagine it is far less defined than the magic of Aerynthia. What we may think of as magical -dragons, flying whales, etc- are just their everyday. When they use the word "magic", they are referring to a broad field of science that focuses on magical energies, their sources, and how to harness them. It has many subfields, such as alchemy (the conversion or purification of various materials), enchantment (permanent spells, usually placed upon items or locations), and divination (predictions of the future, usually only finds the most likely events). Like many fields of science in our world, magic overlaps with other sciences. An alchemist needs have just as much knowledge of chemistry as a physicist needs of mathematics.
Like most fields of science, magic has laws. The only one you will likely need to know for this rp is that magical energy follows the law of conservation of energy. Magical energy cannot be created or destroyed, only converted into a different form. This is why most spells and other magical processes must be powered by components (such as jackelope horns, amethysts, phoenix feathers, etc). Some animals and items (such as gemstones and jackelopes) naturally gather these magical energies, making them optimal sources for magical energy. Spells that take larger amounts of energy require either more components or more focused/pure components (meaning they have more magical energy).
Harnessing magical energy is difficult, often requiring complex runes, rituals, and other processes to be completed properly. The education on these subjects, combined with the cost of components, makes the study of magic very difficult and expensive. It is for this reason that most accomplished mages are wealthy. The common person may know how to cast a few spells, but most are simple, small, and only help with housework or cure a mild ailment.