Rules and Setting Modifications

The World of Shaston is a D&D 5e setting based heavily on Wizards of the Coast's own Forgotten Realms. However, there are several differences between this setting and the rules used in it and those of the default D&D setting(s) and rules. These modifications are listed here, in no particular order - AKA whatever order I think of them.

Elves and Sleep
Elves can sleep, but they almost exclusively choose not to. Dreams are strange and bizarre to elves, seen as twisted and frightening images of the subconscious that they can't control. Certain elven priests sleep and dream so as to receive messages from their gods, but otherwise one would be hard-pressed to find a sleeping elf.

Dragons and Offspring
Chromatic dragons can polymorph into humanoid forms like their metallic counterparts; however, it takes them longer to learn how to do so - it is not an innate thing for them. They use it less to interact with people and more to trick and trap them after they've already entered their lair.

When dragons produce offspring with other humanoids while polymorphed, the result will either be a half-dragon or whatever is the appropriate race under normal circumstances. It is unknown if this is random chance or if the dragon somehow controls it, however it is worth mentioning that chromatic dragons will more often produce half-dragons while metallic dragons will more often produce ordinary humanoids.

Dragonborn, like tieflings, are caused by a draconic ancestor somewhere in the creature's family tree. Unlike with tieflings, dragonborn with two non-draconic parents are extremely rare. Usually, at least one parent must be a half-dragon or another dragonborn. If both parents are non-draconic, it is usually the case that one of them - knowingly or unknowingly - has recessive draconic traits; for example, they may be a draconic bloodline sorcerer.

Necromancy and the Undead
Necromancy is not an inherently evil process. While many necromancers do eventually turn evil and the magic required for necromancy is definitely dark in nature, the idea that the very act of raising the dead can corrupt one's soul is incorrect. In addition, contrary to popular belief, necromancy does not typically deal with the soul. Rather than damaging or controlling a creature's soul in order to raise their corpse, a necromancer will fill the corpse with magical energy, creating a foul mimicry of life but not harming the creature's original soul in any way.

That said, there are forms of necromancy that deal with the soul. Most "good" necromantic spells (like reincarnate, resurrect, etc.) call the soul back from the realm of the dead. As such, the soul is only able to return if it is free to do so, and even then has a choice to remain in the afterlife. This type of necromancy typically fully restores a dead creature to life. However, some powerful forms of necromancy can being a dead soul back without fully restoring it to life, thus creating a strange cross between life and undeath. The unliving are a token example of this, although they are even more unique in that they were not given a choice to be raised or not. Most necromancers are not interested in this type of magic, as it does not fully raise a creature to life, thus failing as a resurrective method, while causing the raised creature to retain its free will, thus failing as a method to create undead servants. Death despises this form of necromancy in particular, as it interferes with the natural order and cycle of life and death in ways that other necromancy does not.