Mewt Idejn

In the beginning, before the Voices called the peoples, Hasira Uovu hated the people, and he whispered in their ears, and the people fought one with another.

— From The Tale of Beginnings

Sapient people have big brains which require them to consume animals for protein and fat and minerals, so from very earliest times, one had to kill to eat, and tools were used to do that. Those tools used to kill for food - like sticks and rocks, could also be used to kill people - the ones who annoyed you or refused to be controlled, or robbed or raped, or if you were evil, the ones you wanted to torture and kill because you thought it was fun. Conveniently enough, these tools could also be used to protect yourself from people who were trying to kill you because you had annoyed them, or refused to be controlled or robbed or raped by them, or because they were malevolently evil and wanted to kill you for fun.
It's very much about people.

Elven Origins

Some time after fists and rocks and knives and sticks, about the time of swords and spears, elves began to experiment with controlling the seemingly random power some had for destroying things without using tools. Not all had this power, but among those who did, a secret ability began to be trained, passed from parent to child as part of the rituals of Heldua. With it, the sorcerer could project a stream of magical fire at something from a distance and damage it, usually killing it if it was alive.
Causing damage to the things you intended to damage took skill. One needed to learn to aim and control the stream, and carelessness often resulted in burning down one's home or the forrest or other structures it was highly inconvenient to lose. If the stream was successfully directed at an animal, there would be meat for dinner. If one's aim was poor, you were probably running from a forrest fire. If you directed it at a person, you could kill them.
This magical power was revolutionary in every sense - it made life much easier for most people, making food more abundant throughout the community and providing an instant means of defense against aggressors. It leveled out the balance of power between those who were physically larger and stronger and the sorcerers who tended to be much smaller and squishier than those without the ability. And, as has always been the case since fists and sticks and rocks, it could be terribly tragic when arguments broke out and the power was used irresponsibly to harm another when it was not needful, or used to oppress others who did not have the skill, or malevolently evil when someone killed another person for fun.

Wizards Doing What Wizards Do

by Terry Cassis using Imagine AI

When humans first encountered elves, they immediately were fascinated by and threatened by the power of these sorcerous beings. Elves were not human. They did not think like humans and did not act like them. Elves were prickly and prideful. They despised humans, and disagreements and even arguments often happened, and the humans virtually always lost. The ability to shoot fire from your hand was a powerful advantage for elves that the weaker humans could never seem to overcome. Once elves realized that the humans did not have innate magic working abilities, they began to capitalize on this advantage economically, socially and militarily. Was a human rude to you? Punish them. Did a human have gold you needed? Take it. Did a human have land you wanted? Band together and subjugate it. It made humans pretty useful to have around in spite of their distasteful attributes.
So human wizards set about doing wizardy things. They studied and thought. They applied first principles. They experimented, and failed, and experimented again. They burned down their own share of forrests until they finally came up with the Mewt Idejn.

The best defense is found in the offense you fear.

— Johann Distepi, Founder of Magetown

Design of the Mewt Idejn

The Mewt Idejn is not a single item, but a class of items with a specific purpose. The core of the Mewt Idejn is a spell that energetically spews fire over a period of time. The physical item that the spell resides in serves several purposes. First, it stores the fire magic that powers the spell. Second, it determines the color, temperature, velocity and duration of the pulse of magic fire. Third, it provides a means for focusing and aiming the magic fire.
The simplest, cheapest Mewt Idejn are disposable, limited use items with a predetermined color, temperature, velocity and pulse duration. These are plentiful and readily available. They come in different grades with different strengths for different purposes,ranging from non-lethal to humans or other sapient beings to lethal. These are primarily used for self defense. They also tend to be stick-like rather than bracelet style as this design is easier to aim accurately.

by Terry Cassis using Imagine AI

The most sophisticated of these devices are rechargable, allow almost infinite variability of the flame characteristics and the stream duration, range and stregnth, and they incorporate aiming assistance to ensure effectiveness. Mewt Idejn used for game hunting or wildlife protection are typically straight rechargable items on the high end of lethality depending on the game being hunted. Sophisticated Mewt Idejn used for self protection are typically of a bracelet style though they may also be wands or even embedded in swords. They are often heavily decorated and may be bejeweled, and are not readily identifiable as Mewt Idejn at first glance.
Humans began to wear and carry these items when interacting with elves, and after a few unpleasant interactions, the elves got the message that they no longer had overwhelming power to hurt the humans and became more tolerable, less aggressive, and respectful neighbors. Then the humans began to wear them all the time, because, well, there are a lot of not nice people in the world, and having one was a good way to not get robbed or raped or killed. Having one evened out the power physically and magically between the weak and the strong, and wearing a Mewt Idejn became particularly prevalent among females and older citizens.
Of course, there are those who are not nice people, and use them to rob or rape or torture, or kill others, and there are people who are irresponsible or stupid and hurt people with them by accident.

Availability in Arrhynsia

In Arrhynsia, the Mewt Idejn is readily available at magic item outlets in every major metropolitan area, and many large towns. Specialty designers create expensive masterpieces which can be worn as jewelry. Smaller communities may or may not have a magic item supplier who carries these items.
The governments of most nations tax these items and heavily regulate them, primarily because governments can never resist the opportunity to collect more taxes, and because they really dislike their governed populations having any power at all to revolt against the abuses of power of those governments. Their objective is to restrict the ownership of these devices to those who work for the government and support their policies, thereby maintaining their grip on power.
But the humans of Arrhynsia still wear their Mewt Idejn to keep themselves safe from people - the ones who try to kill you because you annoy them or refuse to be controlled by them or robbed or raped by them, or the ones who try to torture you because they think it is fun. They wear them to remind their governments that they are answerable to the people they govern.
And they always, always wear them when interacting with elves.
Playing a Mewt Idejn in 5e

The Mewt Idejn takes any form designated by the GM. It must be carried by the user and attuned to them. The Mewt Idejn has 10 charges (engaging 3 targets per charge) of the second level spell Scorching Ray which can be used without a spell slot and without verbal or somantic interactions. The casting time for use of the Mewt Idejn is one action, or one reaction whenever the user is attacked. While the Mewt Idejn is being carried by the user, the user has a +1 on all persuasion and intimidation checks. When all charges are expended, the Mewt Idejn breaks and disappears, and all it's effects on it's user dissipate.
The Mewt Idejn can be used by users who do not have spell casting abilities by expending charges. When used by them, each attack is made using the users Stregnth or Dexterity attack modifier (user's choice), 1d20 + attack modifier + proficiency against the target's spell save DC. On a save the target takes half damage. On a failed save the target takes full damage.
If the user is a spellcaster, the spell Scorching Ray is now added to your spell list (using all your normal spellcasting modifiers), is a prepared spell for you, and does not count against your prepared spells. You may use the Mewt Idejn without expending a charge if you use a spell slot as identified in the spell guidelines for casting and upcasting the spell. Alternately, you may expend a charge of the Mewt Idejn without expending a spell slot.