Magic Tattoos

So this topic has been beaten to death with a stick, starting at 3.5E (feat and equipment, I guess?), creeping into D&D's wayward child Pathfinder (archetype and feat, I guess?), and of course finding a modern home in the homebrewing sphere of 5E.

I don't have any interest in writing more rules for if you get infected when you get tattooed, there are too many of those already. I already wrote about the tattoos barbarians and monks have, so lets use that as a jumping off point.

Acquiring a Magic Tattoo Design:

Magic tattoos are uncommon and unsightly things. You must inscribe in your flesh the arcane geometry in the appropriate materials to warp reality around the nexus of ley lines living on your skin. Finding a way to do this is a pretty rare occurrence, few Magi spend their valuable time researching ways for warriors to get stronger so they can kill more warriors (they are too busy staring at the stars). So when a new magic tattoo is designed it is often by accident or by madness.

Pirate captains and warlords have these special tattoos, not emperors and generals. These are relict knowledge of a savage Age and polite society tends to close their gates and turn their noses the tattooed heathens from beyond the waves who come to their white cities.

Rumor has it you can find magic tattoo designs here (1d6):

1. On the corpse of a long dead Sea King, you have to go dig them up and cut off their skin and take it to a tattooist to be deciphered and transcribed. They are interned on the Ivory Island of course.
2. In an ancient text deep in the archives of one of the Minoan Universities. You'll have to either enroll as a student or break in to gain access, But beware! Those musty old men are steeped in bureaucracy and have deep institutional power behind them, get caught stealing and you'll like never be allowed in the Republic again.
3. Scratched into the dungeon walls of one of the Towers of the Moon by insane prisoners of the Nekros Archanis in their insights of eternal near death. If you ever find yourself in these dungeons it may be worth while to copy the scrawling, but good luck discerning arcane diagrams from the scrawls of a fevered and broken mind...
4. The ruling line of the Wayward Clans of Arsuf often has a clan magic tattoo inscribed once they reach adulthood. Their detractors say that each clan's patron Daemon taught them their tattoo and that its actually a way for the Daemons to manipulate them. Maybe you can go hunting for one of them and kill one of the ruling line? Or perhaps you can bind a Daemon and ask for a magic tattoo yourself...
5. That company officer tattoo of the Steller's Jays, the mercenary company led by the enigmatic Ramsay Steller, is supposed to actually be a magic tattoo. They just rarely have the appropriately skilled tattooist do the ink job, so not many of them actually work. Join up and maybe you can get a copy of the designs if you get promoted, or perhaps you can kill a few and take their hides to be studied.
6. The guild of grandmaster tattooists known as the Seven Sages, are said to know a few powerful magic tattoo designs but they will only tattoo those they find worthy by passing their Seven Trials. (Think of them as like a mix between philosophers and master martial artists, they could probably also teach monks a thing or two about fighting)

Finding a Tattooist and Getting Inked:

This guy will tattoo you, if you're cool enough.

At least an expert tattooist must be employed to inscribe a magic tattoo, and depending on the complexity of the tattoo more talented tattooists must be found (it may be in the party's interest to try and convince a tattooist to move to their settlement and work under their protection, but they'll have to build them a studio).

Once an sufficiently skilled tattooist is found they will have to be given time to study the magic tattoo design and to gather the appropriate materials, this will take around a month and they will require half of the payment up front to acquire the components necessary.

The tattooing itself will take 1-4 months (same as getting tattooed for defense by the different levels of tattooist) of dedicated time every day to be done. This means you will be lying down for 8 hours every day in a quiet studio with a lot of incense and sandal wood burning, a good activity for the Season of Storms when travel is dangerous.

Example Magic Tattoos:

Mechanically magic tattoos are magic items that you can never un-attune from, until you have them removed by some painful or very expensive manner (in 5e, system agnostic they are just magic items). As with mundane tattoos they must be uncovered in order to work. Each tattoo has a minimum "level" of mundane tattoo for the tattoo to work properly.

Remember, every tattoo has to have a really cool story to go with it.

Here are 12 ideas based on the above sources:

1. Aeropos's Pride: Master level tattoo, +5,000 , you can a +2 bonus to your Cha score and the ability to cast Viscous Mockery as a cantrip, using your character level as your caster level.
2. Cassander's Secret: Expert level tattoo, +3,000,  you apply double your proficiency bonus when making a deception check and once per day you can detect whether a statement is a lie or not.
3. Lysimachos's Swiftness: Expert level tattoo, +4,000, your base land speed increases by 10ft and you gain one of the following movement speeds: climb (half max), swim (half max), or burrow (quarter max). This choice is made at the time of tattooing.
4. Demetrios's Hubris: Grandmaster level tattoo, +10,000
5. Stain of Filth: Expert level tattoo, +2,500, you can cast Detect Undeath (as Detect Magic, but it only works on Necromancy magics) at will and you get advantage when parlaying with undead but disadvantage when parlaying with the living.
6. Blemish of the Starless Night: Master level tattoo, +5,000, you bind your soul to your mortal coil and become undead (usually a ghoul). You no longer have to eat, drink, sleep or breath. You also gain a empathetic bond with the Nekros Archanis, driving you to do their bidding in the land of the Sun.
7. Steller's Jays' Insignia: Expert level tattoo, +2,000, you can communicate silently with anyone else with the Insignia within a mile radius. This communication cannot pass through 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood.
8. Mark of the Cresting Wave: Expert level tattoo, +2,500, you gain the limited ability to command water. This lets you create a current out of still water, slowly (10 min/gallon) boil or freeze water and mostly-water-substances, lets you ask water to not drown you quite as fast (double the duration you can hold your breath), and allows you to cast Cresting Wave (as Thunderwave but you must be on or near a body of water) once per day.
9. Mark of the Barbed Harpoon: Master level tattoo, +4,000, you gain proficiency with the harpoon (as trident, but range 30/120), or if you already have proficiency you gain double your proficiency bonus with the harpoon. In addition on critical hits with harpoons opponents are considered restrained until they take a full round to rip out the harpoon which deals damage as normal when removed.
10. Mark of the Lonely Albatross: Expert level tattoo, +2,500, once per day you can extend your arms into long white wings and float to the ground, as the effect of Feather Fall. In addition you can now speak with sea birds.
11. Mark of the Starry Sail: Expert level tattoo, +1,500, you apply double your proficiency bonus to sailing checks and you can never become lost when under a starry sky.
12. Wisdom of the Seven Sages: If you pass their trails the Sages will agree to tattoo you for free as long as you have up to a Master Level tattoo. The tattoo will be of Grandmaster Level has the following properties based on how the trails where overcome:
1. You overcame the trials through shear strength, your Strength score is now 25, unless it was already higher in which case this effect of the tattoo has no effect. In addition once per day you can hurl things (objects, people, yourself) twice as far as you normally could.
2. You overcame the trials through skillful agility, your Dexterity score is now 25, unless it was already higher in which case this effect of the tattoo has no effect. In addition once per day you can get extra slippery and automatically succeed some feat of acrobatics that would other wise be impossible (scale a glass wall, balance on the edge of a knife, the Iron Lotus)
3. You overcame the trials through  steady resilience, your Constitution score is now 25, unless it was already higher in which case this effect of the tattoo has no effect. In addition once per day you can choose to ignore one round of damage, this must be declared before any attacks or damages are rolled.
4. You overcame the trials through cleverness and insight, your Intelligence score is now 25, unless it was already higher in which case this effect of the tattoo has no effect. In addition once per day you can learn one weakness or strength of a living thing from 10 minutes of observation.
5. You overcame the trials through intuition and temperance, your Wisdom score is now 25, unless it was already higher in which case this effect of the tattoo has no effect. In addition once per day you can intuit the honesty of one statement after meditating on it for 10 minutes.
6. You overcame the trials through force of personality, your Charisma score is now 25, unless it was already higher in which case this effect of the tattoo has no effect. In addition once per day you can generate a basic level of communication out of something that generally has no language (golems, eels, trees, clouds, termites, etc). This takes 10 minutes of intense observation and evocative dance.
7. You overcame the trials through dumb luck, you now gain the Lucky trait as a Halfling (When you roll a 1 on an attack roll, ability check, or saving throw, you can reroll the die and must use the new roll). If you already have the trait you reroll on 1s and 2s. In addition once per day you can roll with advantage on any attack roll, ability check, or saving throw even if you have disadvantage.

Mark of the Barbed Harpoon

Mark of the Lonely Albatross

Stain of Filth