@chdarling-tle
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@chdarling-tle
Do you think Draco knows about what the dark mark does? Since it’s implied that he was given it yet He, Crabbe and Goyle never considered using it to summon Voldemort in Deathly Hallows and Draco nor Lucius considered using it to find each other.
Plus we know Lucius kept the darker aspects of the Death Eaters away from Draco. So it wouldn’t surprise me if he ever downplayed the mark by pretending that it was just a weird tattoo.
This is an interesting question about what the Dark Mark actually is, what is does, how you get one, and why.
So the films go in a more tattoo direction (for clarity and aesthetics) while the books do more of a brand / scarification thing. Dark Marks are described as "ugly" and "red," and only "burn black" when they're actually being used. There's also this through-line of Marks "getting clearer" all through Book 4, which could apply to a tattoo, but seems more in line with a scar. An old scar that's faded suddenly looking fresh again? Very creepy. Also, dark magic is often associated with scars (Harry's lightning bolt and "I must not tell lies" scars, George's Sectumsempra scar.) So a more scar-like Dark Mark fits with that. Because of this, I would imagine that the process of getting a Mark is definitely violent, probably painful. Also knowing Voldemort, I'm sure it comes with some sort of ceremony where you have to swear undying loyalty and kiss the hem of his robes or whatever.
In the books, we don't know if Vincent Crabbe, Gregory Goyle, or even Draco Malfoy have Dark Marks at all. One of the big theories after Book 6 was that the "something on his arm" Draco uses to scare Borgin was a werewolf bite, and you'll still sometimes run into Werewolf!Draco truthers. But the movies do give him a Dark Mark, so let's just run with that.
Dark Marks are this two-way magical leash that allows Voldemort to summon you, and allows you to summon Voldemort. Hermione's coins, which are modeled after the Dark Mark, work like this too - her master coin communicates with all the secondary coins, but the secondary coins can't communicate with each other. Voldemort likes it this way: he's the center, and all his Death Eaters are spokes of the wheel. He likes it when they're at each other's throats (that way they can't unite against him...) and will purposefully build dynamics that pit Wormtail against Barty, Barty against the group, the group against Bellatrix, Bellatrix against Lucius... etc.
Voldemort also likes to frame Dark Mark as this great reward he's giving his Death Eaters, when really it's a control mechanism (same thing with Wormtail's silver hand). He'll always be able to locate his Death Eaters... and always be able to hurt them from a distance. Barty's Mark is probably how Voldemort was able to sniff him out while he's invisible in his father's basement, and it's also the reason running is not an option for either Lucius or Draco. Karkaroff tries to run, and we don't know what happened to him exactly... but he's dead in a shack circa Book 6.
If he gave out too many Dark Marks, they wouldn't work as an "inner circle" type reward anymore, so this might be why Voldemort doesn't have that many Death Eaters. Like, at any given time, it's between 20 and 30. He doesn't give a Mark to the Snatchers, he doesn't give a Mark to Greyback. So then what is his criteria?
I think Voldemort only gives out Marks to people who are valuable/dangerous/smart enough to potentially cause problems for him. He can control Greyback just fine by dangling that final piece of acceptance just out of reach forever... but even if Greyback went rouge, so what? He doesn't know anything, he doesn't have any power or social capital. Lucius Malfoy though... if he defected, now Voldemort has a problem.
Draco would have gotten his Mark pretty much the second he turned sixteen, and I think that's not Voldemort's usual MO. Draco is an important piece in a game Voldemort is playing to punish and control Lucius, and that's the only reason he's valuable. It surprises literally every other character in the book when he actually manages to overpower Dumbledore.
So, to answer your questions up top - yes, I think Draco knew exactly what the Mark did, because he would have gotten it in a weird scary ceremony designed to freak out his parents. I'm sure if Lucius and Draco could have used their Marks to locate each other they would have, but that doesn't seem to be how Dark Marks work. And Crabbe and Goyle can't call Voldemort because... I just don't think they have Marks. They're not important enough for Voldemort to care about controlling them, and his plan is probably to string them along the way he does Greyback, requiring them to "earn" their place at his side. Draco probably could have called Voldemort to him in the Room of Requirement... but he was never going to, because at that point he doesn't want Voldemort to win, and is passively resisting pretty hard. But you're right - Crabbe and Goyle absolutely should have realized that Draco was avoiding using his Mark to call Voldemort, and this is very suspicious behavior.
Sometimes I sit down and write a really good fanfiction, and then I reread it and realize its almost a direct quote from the last enemy, and I just stare at it and cry 
I want The Last Enemy to show up on every I've-read-ATYD-and-wanna-read-another-marauders-fanfiction-just-as-great person's doorstep so we'd have a bigger fanbase so I could be unhinged with more people.
My headcanon is that Percy Weasley had a dark mark, for more headcanons like this and further explanation on this one (cause I'll only do it if someone wants to hear it) can be found by going to my asks,,,,, please ask me things, my blog is lonely...
sometimes when you wanna write but your brain is too scattered to do the word wrangling, you’ve gotta trick yourself into flow state by spending the whole morning designing gold leaf dark marks for your totally unnecessary vintage book covers for your totally unnecessary fanfiction prequel series 😂
ok I’m actually going to write now
A Force of Nature
Hermione had always felt proud to call herself a muggleborn witch. Until one day her world was turned upside down with the appearance of someone calling herself her grandmother. Her parents had lied to her. She wasn’t a Muggleborn. She was one of the sacred twenty-eight and the granddaughter of one of the darkest wizards on record. Delve into a story of lies and ancient powers https://archiveofourown.org/works/22982413/chapters/54944245
Looking for a fic where Hermione puts the deatheater tattoo on herself and Draco while they were at a deatheater meeting. They get back to Grimmauld where they are put together on questioning. Which in result she admits to being pregnant through it all.
Anyone?