Crystali do not need to reproduce the same way humans do. This means any couple, group or single Crystali can have offspring. There is no need for their gender or relationship type to come into play.
To have a child entails performing a ritual at a life spring. There are a few of these dotted across Nophra in various regions. The ritual will not work unless intentions are pure and true from all parties involved. Offspring are forever tied to all parties who participated in the ceremony. A child's element will usually be closely related to one of their parent's, but to gain a somewhat distant ancestors' element is not unheard of.
Additionally, a child may gain traits from the life spring they were born at. Nearby settlements, Cultures and environments can play a big role. This can show in a variety of ways, so feel free to be creative with it!
Dragons typically do not need to use these, as they normally reside in places coursing with very pure draconic generational magic, far away from the influence of nearby settlements and tribes. This is one of the reasons their offspring can be so unique, aside from being half dragon. While they don't need to visit them, some still choose to for a variety of reasons.
There are 4 life springs dotted around Nophra, One for each base element. (Water, Fire, Air, Earth) There is somewhat of an elemental influence depending on which spring the ritual is performed at, but it does not mean the child will always be of the spring's element. Also, these springs are highly spiritual places. The people of nearby villages will maintain them and their shrines and pray at them. They are imbued with the hopes and dreams of their people and this often reflects on offspring in a variety of ways.
There are no springs for Light and Dark elements, as their respective gods play a different role in the birth of new life.
The springs are located in the following places:
The shrines are connected via an alternate dimension referred to as 'the lifestream'. Sometimes traces of demigod magic are present and can catch on new life, occasionally granting a seemingly random element.
Mystic Crystali live to be around 500 years old. In extremely rare cases, some elders have managed to double that through meditation that allows them to absorb more magic from Nophra. It is a skill that is extremely time consuming to gain significant results from, so not many do it.
Common Crystali have shorter lifespans, mostly capping off at 300. Similarly to a Mystic's ability to extend their own lives, Common crystali can receive extra magic to extend theirs.
A few things can cause Crystali to die.
If more than ~30% of their crystals are shattered, they will die. Their crystals are very tough so this has to be done intentionally for the most part.
Aside from being able to wield magic, they are soft beings. They are not magically immortal in any way and will die from any grave injury that they cannot physically heal from.