Arcane (5e Creature)

Large humanoid, lawful neutral

Armor Class 16 (chain mail)
Hit Points 85 (10d10 + 30)
Speed 30 ft.

Saving Throws Int +9, Cha +7
Skills Arcana +9, Deception +7, History +9, Insight +7, Persuasion +7, Survival +7
Tools Dragonchess set
Proficiency Bonus +3
Damage Resistances psychic
Senses passive Perception 14
Languages any three languages, telepathy 120 ft.
Challenge 8 (3,900 XP)

Innate Spellcasting. The arcane's innate spellcasting ability is intelligence (spell save DC 16). The arcane can innately cast the following spells, requiring no material components:

At will: vicious mockery
3/day each: dimension door, invisibility

For creatures of their size, the arcane are noticeably weak and non-combative. They can defend themselves when called upon, but prefer to talk and/or buy themselves out of dangerous situations. If entering an area that is potentially dangerous (like most human cities), the arcane hires a group of adventurers as an entourage.

Society. Nothing is known about the arcane's origins; they come and go as they please, and are found throughout the known worlds. When they travel, they do so on the ships and vehicles of other races. Finding such ships with arcane aboard is rare, and it is suspected that the arcane have another way of travelling over long distances.
Contacting the arcane is no trouble in most civilized areas: a few words spread through the local grapevine, through taverns, guilds, and barracks, are enough to bring one of these creatures to the surface. In game terms, there is a base 10% chance per day of finding an arcane, if PCs actively look for one; the chance increases or decreases depending on their location. Arcane never set up permanent magic shops.
The arcane's stock in trade is to provide magical items, particularly spelljamming helms, which allow rapid movement through space. The arcanes' high quality and uniform (if high) prices make them the trusted retailers. They accept payment in gold, or barter for other magical items (as a rule of thumb, costs should be five times the XP reward of the item, or a more valuable item).
The arcane take no responsibility for the use of the items they sell. The arcane will deal with almost anyone. They often make deals with both sides in a conflict, fully aware that they might annihilate all of their potential customers in a region. The arcane have no dealings with neogi, nor with creatures from other planes, such as genies, tanar'ri, and fiends. It is unknown whether the arcane create a wide variety of magical devices, or secure them from an unknown source.
Those dealing with the arcane find them cool, efficient, and most importantly, uncaring. Trying to haggle with an arcane is a chancy business, at best. Sometimes they will engage in haggling with a bemused smirk, but just as often leave the buyer hanging and walk out on the negotiations. They do not like being threatened, insulted, or blackmailed. Those who do so will find it very difficult to purchase reliable equipment. An arcane will not raise a hand in vengeance or anger—there are more subtle ways to wreak revenge.

Ecology. It is not known what arcane do with the gold, gems, and magic they collect. One theory says they need the items for reproduction (the basis for a large number of bawdy arcane jokes), while another links it to the production and acquisition of more magical items. The arcane seem sexless. No young arcane have been reported, and the arcane keep their own counsel.