Fanfic / Cross Cases

Sam Winchester: "This isn't my reality."

Harry Dresden: "What."

Cross Cases is a crossover fanfiction between The Dresden Files and Supernatural, hosted on Archive of Our Own and written by yopumpkinhead. The fic ran from April 2015 to December 2016, concluding with 48 chapters. It takes place between Seasons 10 and 11 of Supernatural and a few months after the events of Skin Game, the fifteenth novel of the Dresden Files. This fic assumes that you have watched/read up to those points, so spoilers pertaining to those series prior to those points will be unmarked.

When Sam Winchester cuts a deal with Lucifer to have the Mark of Cain removed from Dean, he finds a spell laid out in the abandoned St. Mary's convent that teleports him onto Demonreach in the Dresden Files universe, where he is found by the island's warden, Harry Dresden. Soon, Harry and his friends start getting attacked by demons as Sam's associates come looking for him and inadvertently stir up their own trouble, and all the while, Sam's sharing headspace with the Devil.

Body count: 1 human and 10 demons.

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This fanfic contains examples of:

• The Alleged Car: Since the loss of his beloved Blue Beetle, Harry's purchased an old vomit-colored Chevy Caprice, which he despises because it's huge and he can't maneuver it as well as he could the Beetle. It's basically an extra-shitty version of the Winchesters' Impala, and even Sam describes it as worse than Castiel's crapmobile. Somehow, Harry still manages to be pissed off about it when the Denarians melt it down to the frame.
• Ambiguously Human
  • In the Dresdenverse, you don't get to be human and have powers the likes of what Sam displays without also being a Walking Techbane. The fact that Sam looks and feels perfectly human, and both owns a smartphone and can not only get near a computer without blowing it out, but is also comfortable using one immediately makes Harry question Sam's humanity. At times, Harry doesn't assume even the most basic things about him, like how he'll react to waking up in an unfamiliar place, or if he'll kill some ordinary mortals who caught him hustling pool. Of course, if you're familiar with Supernatural, you know already that Sam is just a plain ol' human whose contact with demon blood as a child gave him some enhancements that haven't been tapped in several years at the time of the fic, as well as the current vessel for Lucifer.
  • Dean's visit to the Carpenter house winds up calling his humanity into question by Dresdenverse standards when the house's angelic security force is revealed to have marked his mere presence as a threat under their purview and geared up to smite him. Unlike SPN-verse angels, Dresdenverse angels, including the Carpenters' security force, are unable to interfere with threats acting under free will, which includes humans, the implication being that the Mark of Cain had influenced him enough with its inherent nature as a carnal force of destruction to make him just barely qualify as nonhuman.
• And the Adventure Continues: After Sam, Dean, Charlie, Castiel, and Crowley make it back to their own reality, Lucifer takes Michael (Carpenter's) advice of making his own choices by removing the Mark of Cain from Dean... and then setting it free so it can wreak havoc. And the two brothers set out to save the world once again, this time with their friends right behind them.
• Bash Brothers: In a parallel to Dean and Sam's canon relationship, Harry and Sam take down demons, ordinary mortal pool sharks, the Hell-demon leading the aforementioned demons, and a warlock as parties to every single fight scene in the story, and also scare off Denarians. Sam even notes how much Harry's wisecracks remind him of Dean.
• Big Bad: The demon Patterson summons, Chaxuneudahl, wants to sell Amoracchius to the Denarians. It just so happens that Amoracchius is being held by Harry Dresden, someone Patterson would very much like to get out of his hair, and so it had those demons attack Harry and drag him a few states away to the Denarians. The fact that the Supernatural-verse characters were there was a happy coincidence.
• Big Brother Instinct: Crowley warns Harry to not even seem like he's gotten between Dean Winchester and his little brother. Sure enough, during the fight with Patterson's demons, Dean gets transformed back into himself early and sees Lucifer-as-Sam burning alive from flaming holy oil on the other side of a horde of demons, then starts mowing them down in a mix of love for his brother and Mark-of-Cain-fueled rage with Amoracchius. But when Lucifer whisks Sam away to repair his burned body, all the Mark can think of is to go after Harry, the one who took Dean's Sam from him. And it's implied that if Lucifer had brought Sam back even a moment later, Dean would have set Amoracchius to Harry and destroyed the Sword of Love in the process.
• The Big Guy: Sam is the tallest character in Supernatural at 6' 5" (195cm), a fact that he is evidently used to when he first meets the 6' 9" (206cm) Harry Dresden and is surprised to have to look up at someone for once. He also contrasts against Harry's lanky build by fighting like a brawler, and is, in Harry's words, built like a brick wall. Sam lampshades it in his narration by calling the two of them a pair of scruffy NBA rejects.
  Crowley: "I didn’t think they came bigger than you, but you’ve gone and found yourself a giraffe."
• Bounty Hunter: Harry doesn't buy Sam's claim of being a librarian for even a second, and decides he's most likely a merc who does dirty jobs for the highest bidder, from the way he moves, his weapons, the fact that he's built like a brick wall, and his careful, practiced lack of reaction to anything, supernatural and not. After he and Murphy go through his wallet while he's unconscious, they find his multitude of credit cards and fake IDs, only cementing the assessment in their minds. This isn't really too far off from Sam's (sort-of) actual profession as a hunter, minus the getting hired and paid part.
• Butt-Monkey: Crowley does not have a very good time in the Dresdenverse. He tries to cut a deal with a warlock for his soul and nearly gets locked up on Demonreach while fulfilling his end of the bargain (himself, because he didn't have access to any of his agents that could do it for him), then gets his meatsuit turned into a frog for his troubles. He finds another meatsuit and goes to Sam for help, but Sam with Lucifer's help Force-chokes him and he threatens to kill Crowley before slapping him in demon handcuffs and frog-marching him back. Then Harry lets Alfred get petty and make Crowley trip over sudden tree roots and potholes, fall into puddles, get whacked by tree branches, and walk into swarms of mosquitoes on his way to the teleportation ritual site while gently aiding the others. And he didn't even get the warlock's soul out of this mess!
• Character Tics: Sam has a habit of scrubbing his hand over his mouth when he's thinking, or sometimes nervous. Harry also notices other 'tics' of his, such as pressing his nail into his left palm and apparently looking away at nothing, both of which are related to him being Lucifer's vessel.
• Cold-Blooded Torture: When demons attack Murphy's house, Sam deliberately keeps one of them alive so that he can torture information out of it on who sent them, pinning it down and twisting his demon-killing knife into its shoulder. When Harry finds them, he tells the demon that it'd better answer Sam, because Sam will just kill the demon when he's done.
• Creepy Good: From Harry's perspective, Sam, and later Dean as well. Sam's aura feels "bloody" from all of the people and things he's had to kill over the years, he moves back and forth from "oversized puppy" to "cold deadly fighter" with ease, he's cagey, he has scary powers that border on the impossible in the Dresdenverse, and the things he does over the course of the story only make him scarier and scarier. Harry has trouble reconciling this quiet, cagey, apparently human guy with the fact that he kills things (and sometimes people) for a living, defaulting to thinking of him as a con artist (which he is). Once he's reunited with Dean, the brothers are quick to dehumanize Patterson, treating the situation as a witch hunt as they remorselessly hunt him down like an animal. Afterwards, the two laugh and banter like normal brothers who didn't just kill a man as they drive away with his body in the trunk of their stolen car.
• Cruel Mercy: After Sam allows Lucifer to take him as his vessel, Lucifer lets Sam keep control of his body so that Sam can go back home and tell Dean goodbye. Sam notes in his internal narration that this really does seem nice on the surface, but perceives it as a final "fuck you" so that Sam's last moments as himself and of Dean are of Dean reaming him out for handing himself over to Lucifer, hopefully followed by Dean killing him in an attempt at taking Lucifer with him. This thought keeps Sam lingering in St. Mary's convent, whereupon he finds the teleportation spell.
• Curb-Stomp Battle: The fight with the pool shark's four buddies, versus Harry Dresden and Sam Winchester. After all the unspeakable horrors Harry and Sam have fought and taken down, the poor guys didn't even stand a chance. Harry disarms one with a single aikido maneuver, while Sam easily knocks out the other three in just a few punches. Both of them come out without a single scratch, and according to Harry, the whole thing was over in about six seconds.
• Darkest Hour: There's two in quick succession, each one for a different plotline. The first is for the fic's overarching plot and comes when Nicodemus, Lartessa, and Rosanna have Harry, Sam, and Butters cornered against a U-shaped glass building. Sam finally submits to Lucifer and lets him take control to scare the Denarians away, which leads directly into the Darkest Hour of Sam's arc- Lucifer relinquishes control to Sam after a chat with Harry, leaving him to endure the shame and guilt of having his dark secret exposed to a Knight of the Cross and someone who he had just begun to think of as a friend.
• Deal with the Devil: The fic opens with Sam meeting Lucifer at St. Mary's convent and cutting a deal with him to remove the Mark of Cain from Dean, and to leave Earth alone for the rest of Dean's natural lifespan. In exchange, Sam hands himself over as Lucifer's vessel, and agrees to let Lucifer take Heaven, Hell, and even Earth, because the brothers are so damn tired of having to save it all the time and getting shit on for it. Lucifer is so taken aback he accepts, gladly.
• Demonic Possession: The story opens with Sam allowing Lucifer to have him as his vessel. Lucifer spends the first 2/3 of the story too weak to actually take control of Sam, but he's able to project himself into an illusory body that only Sam can see and generally abuses Sam as he pleases, verbally and mentally. He finally allows Lucifer to take over to scare the Denarians away and to talk to Michael (Carpenter), and proves materially beneficial to Sam by drying and mending his clothes and protecting him from being burned alive by flaming holy oil.
• Did You Just Flip Off Cthulhu?: After Harry learns the truth about Sam, he starts deliberately annoying/pissing off Lucifer to draw his attention away from his host. The first time, Harry tells him off for incapacitating Sam, and Lucifer throws out a Ghostly Chill and insults him (inaudible to Harry), to which Harry responds by giving him a stupid nickname and challenging him to an A/C-off as the Winter knight, singing "Let it Go" badly and off-key to rile him up. Fortunately for Harry, Lucifer just finds it amusing and decides he actually likes Harry too much to crush him, much to Harry's (and Sam's) surprise. Later on, Harry exploits this by making faces at Lucifer's (invisible) projection on the way to Patterson's so that Lucifer's less likely to incapacitate Sam.
• Does This Remind You of Anything?: Sam and Lucifer's relationship is depicted in a disturbingly similar fashion to a severe abusive relationship where the abused party (Sam) is almost entirely under the thumb of the abuser (Lucifer). Lucifer gaslights him, verbally tears him down, annoys him constantly to wear down his patience, and flips back and forth between kind of okay or even beneficial, and moments of horrifying psychic mental abuse. Sam is constantly tiptoeing around him and he instinctively fears defying Lucifer or accidentally saying anything to him that could be construed as an order.
• Double Entendre: When Harry's trying to puzzle out how Sam can have psychic abilities yet can still use technology without blowing it out, he mentions that minor talents can still use computers and such without too many issues. Sam dryly asks Dresden if he's not a minor talent, and Murphy mentions that there's nothing minor about Dresden, which gets some snickers from Sam.
• Drama-Preserving Handicap: Lucifer is prevented from just taking over Sam and dealing with things his way because of the risk that doing so would attract the attention of the Uriel of the Dresdenverse, breaking the cold war that exists between Uriel and the Lucifer of this universe and freeing up Uriel to use his full power against Lucifer.
• Drives Like Crazy: Dean, in this story, as a result of the Mark of Cain making him aggressive. When he drives Harry and Sam to the final showdown, he drives at least 15-20 miles (24-30 KPH) over the speed limit at all times, runs red lights and stop signs, turns so fast he brings the side wheels off the road, and generally makes Harry fear for his life, while Sam sways and rocks with the ride, entirely unfazed. When they get there, they reluctantly hand the car over to Bob, who noisily revs the car up... and then slooowly pulls away.
• Evil Cannot Comprehend Good: At the end of the story, Lucifer finally gets to talk to Michael Carpenter. Michael's words amount to telling Lucifer that he could just not do the evil others expect of him, that he could simply make his own choices, and he's so deeply stunned and taken aback that he just screams in his True Voice, shattering everything in Michael's kitchen, and flees.
• Evil-Detecting Dog: Both of Harry's pets get in on the action- first, Mister hisses at Lucifer's projection (invisible to all but Sam and possibly Harry's Sight) when he gets too close to Murphy despite having accepted belly rubs from him earlier, and then Mouse threatens the Mark Of Cain-bearing Dean to not try anything funny when he pays the Carpenter house a visit.
• Evil Is Petty: Lucifer's illusory form is constantly needling at Sam, insulting him, throwing out snide remarks simply to remind Sam he's there, kicking the back of his seat when he's in a car, drumming his hands on Sam, and generally screwing with him, in addition to the mental and emotional abuse. The little things have the effect of wearing Sam down and edging him towards submitting to Lucifer.
• Exact Words: In typical Crowley fashion, he provides Patterson with a binding circle that can hold an archangel to help Patterson contain Chaxuneudahl, but neglects to clarify that this binding circle can only hold an archangel and is just a burning circle of fire to everything else.
• Fire-Forged Friends: Nearly every development in Sam and Harry's brief friendship is brought upon by one of the fic's several fight scenes, each one bringing them closer together (and also revealing something new and scary about Sam in the process).
• Flat "What": As shown in the page quote, total incredulity is Harry's reaction to Sam claiming he's from an alternate reality.
• Forced Transformation: Doctor Patterson is a budding warlock with an unfortunate tendency to transform his enemies and sometimes allies into frogs or toads once they've seen something they shouldn't have, or simply outlived their usefulness. And that includes Dean, Charlie, Castiel, and Crowley.
• Glowing Eyes of Doom: When Harry riles Lucifer up the first time, Lucifer seizes control of Sam's body and threatens to take on all of Heaven if it means he'd get to rip Harry apart atom by atom, making Sam's eyes glow solid blue.
• Good Old Fisticuffs: In contrast to Harry's aikido style of fighting, Sam's an out-and-out brawler with the sheer size and strength to back it up, easily taking down common thugs with just a few punches.
• Hazy-Feel Turn: Lucifer at the end of the story, after realising thanks to his experiences in the Dresdenverse, a talk with Michael Carpenter, and a heart to heart with Sam that he can change. Of course, the way this manifests is still pretty standard Lucifer behaviour. Turns out that the Darkness equates to the contamination of the Outside, which the Mark of Cain is designed to hold back. So, when he takes himself off the board and unravels the Mark entirely, he opens the door to the Darkness and sticks a very solid middle finger up to SPN!God.
• If You Ever Do Anything to Hurt Her...: Non-romantic example: when Harry has to leave to go talk to some people, but doesn't want Sam around and also wants him under supervision, he winds up having to leave Sam with the injured Murphy. Not knowing what Sam even is at this point, he tries to get Sam to swear on his power that he won't hurt Murphy, but isn't quite convinced that it worked, so he adds a threat before he leaves.
  Harry: "You hurt Karrin, an alternate reality won’t be far enough to run. Understand?"
• Insistent Terminology: From Sam's perspective, all magic users are witches, and he habitually keeps referring to Harry as a witch even after multiple corrections from Harry. In the Dresdenverse's magical community, 'witch' is a term that has largely fallen into disuse ever since the Salem Witch Trials and is now only occasionally used to refer to minor talents, and a minor talent Harry is not.
• Invisible to Normals: When Castiel and Dean pay a visit to the Carpenter house in their search for Sam, Cas stops some distance from the house to talk to the angels guarding the property, which he can see and hear just fine. However, no one else can, and most can't even tell they're there, leading to Cas just looking like he's talking to nothing. Dean passes it off as him just being loopy from the all-nighter he pulled the previous night, leaving out that he's kind of like that all the time. When they leave, Cas mentions that when Dean met Mouse, three of the angels put their swords to his throat, ready to kill him if he had done anything to that dog, and he had no idea.
• Last-Name Basis: In Sam's dialogue and even narration, he defaults to referring to everyone new that he meets over the course of the story by surname and usually title, including Harry. Murphy even becomes 'Ms. Murphy', and he only ever calls Harry 'Dresden', despite striking up a pretty good friendship with the guy.
• Lecherous Licking: When Sam finally submits control to Lucifer, Lucifer-as-Sam explains their "arrangement" to Harry, licking his lips in a way that Harry describes as obscene.
  Lucifer: "I save his brother, and in exchange, I get..."
  Harry, narrating: He licked his lips, the gesture somehow obscene. My skin crawled and I suddenly badly wanted a shower.
  Lucifer: "Him."
  Harry: "There are about six bajillion different kinds of wrong with that."
• Magic A Is Magic A: Despite the various differences in the rules of magic between the two universes, the angel-banishing sigil works on Denarians as effectively as it works on the angels of Sam's home universe.
• Metaphorically True: When Harry asks Sam what he does for a living, Sam says he's a librarian. It's an adequate description of his preferred profession as a Man of Letters, but it omits his other gig as a hunter of the supernatural, and ultimately gets Harry more suspicious of him. In general, Sam prefers his lies to have at least a grain of truth to them.
  Harry, narrating: "I didn’t buy the librarian thing for a second- what librarian is built like a brick wall, moves like a hunting cat, and carries a knife and a gun?"
• Mugging the Monster: After Sam hustles a pool shark out of all of his money, the guy goes after Sam and Harry with his buddies in tow, and pulls a gun on the two. Harry and Sam make short work of them without any magic or supernatural stuff at all, cementing their Bash Brothers partnership.
• Original Flavour: Somehow, this fic manages to feel like a perfect combination of installments of both parent works at the same time. The sections written from Harry's POV align perfectly with his narrative voice in canon, and the plot is paced well and twisty enough to feel like an actual Dresden novel, with even the length, number of chapters, and timescale falling within normal range for the series. Even the title follows the Dresden format of "punny title of two words with the same number of letters". And on top of that, the sections from the perspective of any of the Supernatural-side characters hew closely to their canon characterizations and somehow manage to feel like an episode of Supernatural whose events slot in well with both the ending of Season 10 and the start of Season 11, without ever once feeling out-of-place with the sections mimicking a Dresden novel. There's only one OC of note- the main antagonist -and even they fit nicely into the canon of Dresden, complete with their history with the protagonist being something that could totally be present in canon. It's quite remarkable to see.
• Outside-Context Problem: Sam and the bits of Supernatural worldbuilding he brings with him are a complete enigma to Harry throughout the story. Harry has no idea what Sam even is for most of the story and assumes that he might not even be human, given that he's powered without being a Walking Techbane. At times, Harry doesn't assume even the most basic things about him, like how he'll react when waking up in an unfamiliar place, or to a new, non-Harry person, or if he'll kill some ordinary human pool sharks who caught him hustling.
• Painting the Medium: Alfred Demonreach apparently talks in all-caps without quotation marks, which treats his dialogue almost as part of the description of the area, fitting for a living island.
• The Paladin: Presumably because Dean, despite bearing the Mark of Cain, is also the Righteous Man, he's able to wield Amoracchius properly and summon its holy power in the name of love for his brother to mow down a bunch of demons, effectively becoming a Knight of the Cross for all of five minutes. It gets subverted a moment later when the Mark nearly has Dean set Amoracchius to Harry.
• Playing Drunk: Sam gets some money his first night in Dresdenverse Chicago by way of his usual scheme of hustling pool and pretending he's drunk. His act is so good he even fools Harry at first, and from Harry's perspective, if he could fake being drunk that well, who's to say everything else about him isn't just an act?
• Power-Strain Blackout: Sam passes out after using his psychic abilities to kill some demons that were about to tear Harry's throat out. It was the first time he'd done so in years, and he hadn't had any of the demon blood needed to power those abilities safely.
• Psychic Nosebleed: Seems to have happened as Sam had his Power-Strain Blackout after calling up his powers for the first time in years with inadequate demon blood- which is to say he's had none.
• Psychic Strangle: Sam (with Lucifer's help) pulls this on Crowley using his demon-killing psychic abilities, saying that the next time he saw Crowley, he would kill him. He likely would have gone through with it had Harry not intervened.
• Shell-Shocked Veteran: Sam's POV is full of self-loathing, which Lucifer is all too happy to take advantage of as easy fuel for tearing his host down. During their brief not-soulgaze, Harry gets a taste of some of what happened to Sam during his imprisonment in the Cage that nearly knocks him off his feet, and immediately pegs him as a survivor of abuse after Sam is given his body back the first time Lucifer takes control. In Harry's words, Sam looked like he expected Harry to hit him, and like he thought he deserved it.
• Shout-Out: Dozens, considering Harry Dresden is narrating much of it. Of course, Sam gets in on the action, too, courtesy of his long-time proximity to fellow Pop-Cultured Badass Dean.
  • Like most post-S1 episode titles in Supernatural, nearly all of the chapter titles in this fic are direct references to pop culture. In particular, five chapters reference The Wizard of Oz- "The Wonderful Wizard of Demonreach", "Not in Kansas Anymore", "Somewhere Over the Portal", "The Wicked Witch of the Windy City", and "Follow the Icy Brick Road". The three chapters that form the end of the second act ("Fire on the Mountain", "Run, Boys, Run", "The Devil's in the House of the Rising Sun") plus the earlier chapter "Devil Deals the Cards" all reference "The Devil Went Down to Georgia" by The Charlie Daniels Band. Harry also makes Lucifer the butt of a joke that references the song.
    Lucifer: "You're willing to bet your life on that?"
    Harry: (Deep South accent) "Well, my name's Harry, and it might be a sin, but I'll take your bet, and you're gonna regret, 'cause I'm the best there's ever been." (shit-eating grin)
  • There's several to Harry Potter on the Supernatural cast's part. The first time Harry tells Sam he's a wizard on the boat ride off the island, Sam mentions that if Dean were there, he'd be cracking "yer a wizard, Harry" jokes the whole way back to the docks. Later on, Sam asks Harry if he can Apparate, and he says no and adds that they don't do the stupid fireplace powder thing, either. And then when Dean tries and fails to silently signal their strategy to Harry, Dean bemoans in his narration that apparently Hogwarts in the Dresdenverse doesn't teach military hand signs.
  • When Sam tells Harry and Murphy that he's a hunter, Murphy replies, "Like, you kill Bambi?" Sam snarks back that that sort of hunter should be killing Bambi's mother instead.
  • Sam mentions that the last time he got sent to an alternate reality, Raphael had to open up a way for them to get back home from the other side. Harry says, "The ninja turtle, or the painter?"
  • After Sam hustles a pool shark out of his money, the pool shark's two buddies show up to back him up, and Harry narrates that if they were wearing goggles and overalls, they could have been the spitting image of Stuart and Dave.
  • Yet another one from the pool shark hustle- the shark threatens Sam and Harry to give back all of the money Sam hustled out of him, to which Harry replies, "Or what? You’ll challenge us to a battle of wits? Sorry, I left my iocane powder at home." Sam's the only one who gets it.
  • Later on, much to Harry's surprise, Lucifer quotes The Princess Bride when intimidating the Denarians. When Harry mentions it afterwards, since most supernatural nasties in his reality have zero awareness of human pop culture, he replies, "Are you not entertained?"
    Nicodemus: "Impossible..."
    Lucifer: "You keep using that word. I do not think it means what you think it means."
  • Harry learns that "Lucifer" actually translates to "morning star", making "Lucifer Morningstar" translate to "Morningstar Morningstar". Lucifer tells him not to make any Moon Moon jokes, but Harry doesn't know his internet memes.
  • Crowley decides to nickname Harry Slenderman.
  • A couple to Star Wars, as well. When Crowley catches up to Sam, Sam (with Lucifer's help) immediately starts Force-choking him, complete with the hand motion. A bit later, when Sam insists he's okay after Lucifer went after him and that it's nothing, Harry insists that "nothing" doesn't leave a man shaking like a stormtrooper bringing bad news to Darth Vader.
  • The stormtrooper line is followed up with Harry calling Lucifer out on his BS, and responding by throwing out a Ghostly Chill. Harry challenges him to an A/C-off and uses his Winter Knight powers to make the air even colder, all while badly singing "Let it Go" and riling him up even more.
  • When Harry brings Crowley and Sam into Winter territory in the Nevernever, he explains that they have safe passage as long as they behave because he's the Winter Knight, but hides the fact that there's enough asterisks attached to that for a Pratchett novel.
  • Harry calls a demon that looks like it's made of lava Magmar.
  • Before the final confrontation, Harry says, "Autobots, roll out," which nets him a grin from Dean.
• Spotting the Thread: Dean and Castiel pay a visit to the Carpenter house to try and find Sam, and Murphy answers the door. Dean uses his usual FBI agent impersonation schtick, and Murphy plays along for a bit before going, "A case? Wow, you do almost sound like a Fed." He denies it, and she replies that he looks an awful lot like a Winchester, having seen the photo of him that Sam keeps in his wallet.
• Switching P.O.V.: The story's main POV characters are Harry and Sam. Harry's POV offers an outside perspective of Sam that sees him as a cagey Mack truck of a man with scary powers and the eyes of a killer, and Sam's POV offers valuable insight into his seemingly bizarre behavior as well as Lucifer's character arc. Dean, Charlie, and Crowley also get a couple scenes to themselves. If it weren't for the non-Harry POVs, a reader unfamiliar with Supernatural might be forgiven for thinking Sam was some kind of magically souped-up Criminal Minds-grade psycho, not Troubled, but Cute "Puppy-Dog-Eyes" Sammy.
• Take Away Their Name: Lucifer admits that "Lucifer" isn't even his original name; God took away all knowledge of his original name before he was banished to the Cage, and not even Lucifer recalls what he was called at first.
• This Is Reality: Played with a bit when Murphy's house gets attacked by demons and she says, "We were supposed to watch bad TV, not be in bad TV."
• Villainous Rescue: Lucifer intervenes when the Denarians have Sam and Harry cornered, taking over Sam and profoundly disturbing the Denarians - and Harry as a bonus.
• Vocal Dissonance: Downplayed with Sam- when Harry first hears him speak, he notes that Sam's voice is surprisingly light for such a big guy.
• Walking Techbane: Harry gets fairly envious of Sam's ability to both have scary psychic powers and use laptops and smartphones without blowing them out, providing them with valuable information for their investigation into the demons. For once, he'd like to be in Star Trek rather than Lord of the Rings. Sam's also bemused and fascinated by Dresdenverse wizards' inability to use technology.
  Sam: "So I checked the phone’s call logs. It had two incoming calls, both from the same number. It’s a 610 area code, which is a suburb of Philadelphia called Gladwyne-"
  Harry: "How do you know that?"
  Sam: (blank stare) "I Googled it. The phone has a data plan."
  Harry: "...Oh."
• When He Smiles: Both Sam and Dean are in bad places in their canon arcs and aren't up to smiling. Dresden remarks how much younger Sam looks when he smiles and laughs, like any other thirtysomething guy joking around with friends, and once Dean's had the Mark of Cain removed, he grins at Sam, a smile Sam hadn't seen Dean make in two years and thought he'd never see again, as the brothers set out together to save the world once again.
• Wrong Context Magic: The magic systems and cosmology of the Dresdenverse and Supernatural are ridiculously incompatible and are an endless source of headaches for both parties. For one thing, many supernatural nasties in the Dresdenverse can be counted on to not be able to lie, to always uphold their end of a bargain, and to be bound by a litany of non-interference rules including, but not limited to their inherent natures and the Unseelie Accords. Supernatural-verse nasties are most emphatically not, will openly and freely lie and deceive mortals to their own ends, and can be just as conflicted as humans, a revelation that freaks Harry out because he counts on those limitations when dealing with nasties powerful enough to crush him like an ant. Blood Magic in Supernatural also doesn't have the voodoo-esque qualities it has in the Dresdenverse, and true names and swearing on one's power are unheard of and do absolutely nothing. On the other hand, psychic abilities like Sam's are not a thing in the Dresdenverse, and Supernatural-verse magic doesn't blow out technology.
• Wrong Time-Travel Savvy: Based on the idea of travelling to alternate universes being a different form of time travel, this essentially applies to Harry's initial reaction to learning that Sam is from an alternate universe. He assumes that "alternate universe" just refers to the kind of universe where a specific part of history changed, such as a world where Harry Dresden was never born, but everything else he understands about the world still applies. However, he is later informed that "alternate universe" could involve a divergence taking place so far back in the past that the very rules of magic have been changed as well, with the result that Dresden can't be certain Sam's opponents will play by the rules he relies on to keep himself ahead of his enemies.
• You Have Outlived Your Usefulness: After Crowley delivers Amoracchius to Doctor Patterson, having stolen it from Demonreach and nearly gotten locked up by Alfred, Patterson transforms him into a toad and shoves him into a terrarium... alongside the dozens of other people Patterson's done this to.
• You Remind Me of X: Although it's never verbalized, Harry reminds Sam of Dean during happier times with his constant wisecracks and quiet concern for him, and it's the driving force of their friendship. On the road trip to Pennsylvania, Sam even narrates that he could pretend it was Dean in the seat next to him, and the way Harry stirs up Lucifer, between his sense of humor and his shit-eating grin, remind Sam so painfully of Dean he can't look. Even early on, Sam unconsciously slides himself into patterns and interactions with Harry that mirror ones he's made with Dean. Commenters on the fic also noticed parallels between Sam and Harry's vampire half-brother Thomas Raith- both have deep ties to demons with similar inner turmoil over it, are the more reserved and depressive one in their respective duos, and have easy, graceful movements and appearances that make them more approachable.

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