Did You Just Scam Cthulhu?



"Even devils should beware when bargaining with Thanos of Titan."

- Thanos, Infinity Crusade

So, you've got this Chessmaster, Magnificent Bastard or what have you. People are his playthings in any scheme he concocts. But now it seems that he's up against a deity or other supernatural entity... whats this? Did this mere mortal just turn the god into another chess piece to manipulate?

That is the essence of Did You Just Scam Cthulhu? - a Xanatos Gambit, Gambit Roulette, Batman Gambit or other scheme concocted by the resident Magnificent Bastard ends up involving the manipulation of a supernatural entity, deity, etc. by a mortal. Such a plan may include the deity from the outset, or the deity may be integrated into the plan along the way.

This trope may intersect with Did You Just Punch Out Cthulhu?, especially if said Eldritch Abomination ends up coming off worse for wear as a result of the plot.

See Evil Is Not a Toy when someone attempts to invoke either this trope or make a Deal with the Devil, but fails.

Anime and Manga

 * In Death Note, Light, world champion of the Gambit Roulette, manages to manipulate
 * In the Haruhi Suzumiya novels, Kyon forces to back down by threatening to  Essentially, Did You Just Blackmail Cthulhu?
 * Lelouch of Code Geass manages to . Although the scene could be read as the entity doing this willingly, it spawned the Memetic Mutation.
 * Izaya Orihara of Durarara fame, who screws with everyone every chance he gets. Celty and Saika included.
 * Neon Genesis Evangelion executes this beautifully. The Angels are coming to merge with Adam and wipe out humanity. However,  And the Angels are none-the-wiser...
 * In Puella Magi Madoka Magica,  Nice job, Kyubey.
 * Bonus points because the one who scams Cthulhu
 * Of course, since this example's Cthulhu  some have theorized that he "fell for" the scam on purpose, and everything was just as planned, or at least a favorable outcome in a Xanatos Gambit.
 * In Saint Seiya: The Lost Canvas,
 * In Saint Seiya: The Lost Canvas,

Comic Books
""HAH! For all their supposed omnipotence... Even gods can be conned!""
 * In Preacher (Comic Book), Cassidy pulls off a clever scam which results in and . Yes,.
 * John Constantine from Hellblazer is a master of this trope. In what's possibly his Crowning Moment of Awesome, he sells his soul to two of the most powerful demons in Hell at once, which would force them into a war with each other, leaving them no choice but to cure his terminal lung cancer and keep him alive. And then he flips them off. The logic being that if he dies someone has to claim him, and since both of the Fallen has a claim to his soul, just giving it up to the other would be a sign of weakness. And if they actually went to war with each other over it, Heaven would take advantage of the chaos and invade. Mind you, this whole thing backfires when the First of the Fallen just decides to kill his fellow rulers and come after Constantine himself...
 * Then there's the reason the First of the Fallen did this: John had found out that his dying friend Brendan had sold his soul to the First of the Fallen. Five minutes before Brendan's soul ended up in the First's clutches, John suggested they share a toast; Brendan's had this magical working going that turns an underground spring into pure stout. John and the First shared a drink, then John revealed the spring was blessed by a saint, so technically, the base of what the First just drank was holy water. And then the spell expired, and the First had a glassful of holy water in his gut, disrupting his body long enough for Brendan to slip away to Heaven.
 * 2000 AD: Cassandra Anderson manages to make Satan blow himself up by forcing himself into a Douglas Adams-style self-contradiction.
 * The Magus' Batman Gambit in The Infinity War miniseries involved the manipulation of some of the Marvel Universe's most powerful cosmic beings, from Galactus up to Eternity and even the Living Tribunal.
 * And he himself was outmaneuvered by Adam Warlock and Thanos of Titan.
 * Speaking of Thanos, he also at one point literally scammed Mephisto. "You wanted a cosmic cube but didn't specify it had to be functioning..."
 * Wolverine, of all people, arguably outdoes them both in a What If issue, "Newer Fantastic Four". Thanos is in possession of the Infinity Gauntlet, with Mephisto as his advisor, and Wolverine outwits them both by manipulating Thanos' love of Death against him.
 * In Watchmen, 's master plan involves the manipulation of pretty much the entire rest of the cast, up to and including Dr. Manhattan, an energy being of unimaginable power who can normally see the future as clearly as he can see the present. This is justified, as used tachyons to block Manhattan's sight.
 * Black Panther, being the Chessmaster he is, pulled this off with Mephisto. The Black Panther pledged his soul to Mephisto in exchange for Mephisto agreeing to depower an enemy of the Panther's that he had given great demonic power to. Mephisto lived up to his end of the bargain, and so did the Panther...but when Mephisto tried to claim the Panther's soul, Mephisto found that it was linked to the souls of the Panther God and every single previous Black Panther warrior in existence, whose sheer goodness threatened to destroy him. Mephisto requested that the Black Panther agree to release him from the pact, and the Panther agreed.
 * In DC Comics' Underworld Unleashed, the Trickster, in a Heel Face Turn, managed to scam the Devil.
 * In Fables, Jack Horner played poker with the Devil during the Civil War. He cheated and won, keeping his soul and winning the Devil's Bag of Holding.
 * In Emperor Joker, Mr. Mxyzptlk decides to give The Joker 1% of his power to see what he would do with it, but Joker tricks him into giving 99.99%.
 * Which makes it fitting when Superman defeats him by turning Batman into a Mind Virus (the Joker's obsession with Batman keeps bringing him back and his fear when Superman points out he can't control it makes Batman ever larger and more ominous until the Joker is overwhelmed.)
 * Galvatron in the Marvel Transformers comic pulled one on Primus, making him believe Autobot and Decepticon alike had finally put their differences aside for the greater good, all so Galvatron could take revenge on Unicron.


 * This was somewhat easier than it sounds, as Primus had become so senile that he didn't even notice Unicron's approach until Unicron was right in front of him, and even then it took Ironhide to actually point it out.
 * In Triumph and Torment, Doctor Doom manages to trick Mephisto into doing what he wants.
 * Hawkeye manages to beat the Grandmaster, one of the Elders of the Universe, (who was at the time pitting the Avengers (or Captain America (comics) and Hawkeye, the only two still alive) in an endless series of games to the death) by convincing the Grandmaster to engage in a game of chance to make it more interesting. Hawkeye, of course, wins. He did, after all, cheat.
 * Loki has done this several times.
 * In Queen Sonja #20, Evil Sorcerer Thulsa Doom tricks an Elder God into giving him enough of its power that he is able to kill it.

Film

 * Davy Jones gets this in Pirates of the Caribbean, although who it is that actually scammed him is up for debate. It took the combined conflicting efforts of possibly the three smartest/wittiest/cleverest Brits in the Caribbean to
 * The way the heroine from the first Wishmaster movie gets the best of the evil Jerkass Genie. He can't grant a wish that directly affects him, so she can't just wish that he stuffs himself back in his lamp. She's down to her third and final wish, and after she makes that wish he'll be free to run amok and destroy the world, and he's forcing her to take action by murdering and torturing people around the heroine. So, with some clever thinking, she comes up with a wish that will work: she wishes that a specific crane operator hadn't been drunk on the job a few days ago. That crane operator had dropped and destroyed the statue that the genie had been trapped inside of, so the wish undoes everything the genie had done and winds up with him imprisoned again.
 * Aladdin manages to trick his newfound genie servant into freeing him from a sealed cavern without making a wish by prodding the genie's ego, and gets away with it. Later on, when Aladdin is drowning and couldn't reasonably wish for rescue, the genie just takes it for granted that he would wish for it and does so, still counting it as a wish (he takes Aladdin "nodding" as a yes, though this was just Aladdin's head was dropping from lack of oxygen). And at the end of the movie,
 * In the film version of Coraline, the eponymous character does this to the Beldam, the demonic master of a pocket universe who needs to consume the souls of children to live. Frustrated with a boring life and uncaring parents, Coraline is enticed into the Beldam's world which appears as an ideal version of her own home and family. The kicker comes when
 * That happens in the book as well, although the movie makes Coraline's plight more desperate.
 * In Constantine, the film version of Hellblazer, the titular character manages to defeat the film's Big Bad by attempting suicide, knowing that Satan will personally come to collect his soul since suicide is considered a sin. He then bargains with Satan by telling him about the Big Bad's plot to overthrow him, in return for letting a wrongfully damned soul go to Heaven. Satan then realizes too late that Constantine had just performed a self sacrifice, which would allow him to go to Heaven as well. Satan instead resurrects Constantine and cures him of his lung cancer in hopes that he will sin again.
 * In Bill & Ted's Bogus Journey, the boys first attempt to escape death by giving the Grim Reaper a wedgie and running. When they get cast into Hell, they win their souls back and continue on their quest to stop the Big Bad by challenging the Reaper to games like Battleship and electronic football (which he doesn't play, unlike chess) that they're experts at.
 * In The Avengers, Black Widow pretends that Loki's taunting is affecting her more than it actually is (she even pretends to cry). In his arrogance, he makes a comment that allows her to figure out his scheme, and she thanks him. The look on the God of Lies' face when he realizes he's been tricked is priceless.

Literature

 * "The Devil and Daniel Webster".
 * In the Backstory of David Eddings' The Belgariad, the prophet Gorim managed to shanghai UL, the Father of all the Gods. Initially, UL was not a part of creation, and abstained while his sons (also Gods) created the world. After all of the Gods had chosen a race of humans that pleased them as their chosen people, there were some humans left over, the Godless Ones, who languished without a God. One among them, Gorim, managed to find UL and shame him into becoming their God (and also the God of all monsters, those creatures who were imperfect because UL did not participate in their creation). Fairly impressive, overall.
 * And he did it basically by sitting there and waiting. For several hundred years. The mention of it came at the time when Belgarath and his Master (One of those gods behind the creation scheme) were unable to find UL and his people. Belgarath wonders if he perhaps abandoned them again since the new Gorim was particularly irritating.
 * Janus from the book Maledicte
 * In the Uplift series, every scam Earth clan tries to pull on the ancient, Sufficiently Advanced Aliens backfires, until the very end of the series when they manage a doozy... accidentally, with a lie so ridiculous they never expected it to do more than buy them a few seconds.
 * Even more impressively, what actually clinched the deal wasn't a deception at all, but the enemy misinterpreting a genuine offer of.
 * In Lord of the Rings: Sauron the chess GRANDmaster of Middle Earth was outwitted by the Xanatos Gambit directing him away from Frodo. It helped that Evil Cannot Comprehend Good.
 * Happens to an extent in The Silmarillion- specifically, the story of the Downfall of Numenor, where Sauron essentially manipulates Eru Iluvatar into destroying the Numenorean empire for him. Also subverted in that Sauron only intended for the Valar to get involved, and the amount of power Iluvatar was packing was enough to kill Sauron as well. Of course as anyone who's read The Lord of the Rings could tell you, Sauron came Back From the Dead, and at any rate it's impressive to set up a situation where God wipes out your enemies for you in a 'verse where God is both competent and good.
 * In the second book of the Xanth series, Bink wonders if his magical talent of actually manipulated events so that the Source of All Magic  decided to play nice in the end and not destroy everything.
 * In one Discworld novel, Cohen the Barbarian has to roll a 7 with one six-sided die. Naturally, being a Hero, he takes the most awesome method and cuts the die in two while it is spinning in the air, rolling a 7 and cheating Fate at the same time.
 * Notably, he drew inspiration from an in-universe version of the Gordian knot story, which at the time his companions declared to be cheating (Cohen himself was a little more introspective about it). He must have reckoned there's no reason to play fair with gods, who aren't known for their tendency to do so.
 * Another Discworld example, Granny Weatherwax once cheated Death at a card game. Then threatened him. Though he let her win, because he's just that kind of guy, and because Granny Weatherwax is no one to be trifled with.
 * In one short story by Brian Jacques (yes, That one), a kid traded his soul so he could lie better, and ended up convincing the devil he's illiterate, voiding their soul contract, and got an angel to agree to come over to his house for cake - the latter implying he wasn't using his supernaturally-enhanced lying skills.
 * In the Larry Niven short story "Convergent Series", a man deals with a demon he's semi-accidentally summoned by.
 * Another short story, "That Hellbound Train", features a protagonist who just barely manages to outwit Satan after trading his soul for a watch that can stop time. He goes through his entire life, never finding the perfect moment, and as he's dying the Devil tells him that he's given the same watch away dozens of times.
 * The Devil and Simon Flagg: A mathematician makes a bet that the devil can't answer one question. The devil tells him that paradox and Logic Bomb questions are forbidden, so the mathematician gives him a question that must have a yes or no answer: he asks him to either prove or disprove Fermat's Last Theorem.
 * Fermat's Last Theorem was proven in 1995.
 * On the other hand, because viewers generally aren't geniuses they tend to have Small Reference Pools. Whilst Fermat's Theorem is quite famous, many other complex mathematical questions are not. Some are sufficiently esoteric that even establishing whether they have a definite answer let alone working out what the answer would be might be impossible. Asking the Devil to prove or disprove P=NP might be a good start, but there are still things like the Millenium Prize problems which may be more than fiendishly difficult.
 * In His Dark Materials, Mrs Coulter successfully lies to of all creatures, who is explicitly stated to be able to read her heart and/or mind, by manipulating his desire to be corporeal.
 * The men of the city of Gibil do this to the gods all throughout the story of Between The Rivers by Harry Turtledove. The Crowning Moment of Awesome came when Sharur performed a Fake Defector gambit to fool the enemy god Enimhursag, so that Enimhursag believed that Sharur was betraying his home city, Gibil, against their hated enemies, the city of Imhursag. And Sharur successfully deceived the god even though he had to invite Enimhursag read Sharur's mind to see if he was lying.
 * Belisarius Series had several medieval Europeans able to outwit Link; a superrobot from millions of years in the future. Most notably Belisarius but also Damadora and Narses. Narses actually managed to deceive Link looking right in her face.
 * American Gods has

Live Action TV

 * Happened in Star Trek multiple times, with godlike beings practically being a franchise staple.
 * The Seventh Doctor vs. the Gods of Ragnarok in the Doctor Who serial The Greatest Show in the Galaxy. Assuming you don't count the Doctor in the Cthulhu category.
 * In Hercules: The Legendary Journeys, Autolycus, King of Thieves, once managed to steal Hermes's winged sandals right off of his feet.
 * Both Londo and Sheridan manage to do this to the Shadows in season four of Babylon 5.
 * Angel manages to manipulate the Circle of the Black Thorn for most of Season Five.
 * Stephen Colbert has a segment called "Cheating Death with Dr. Stephen T. Colbert, DFA." The graphic shows Stephen in a lab coat playing chess with Death. He cheats.
 * A magnificent example: "I of Newton" from the 1980s revival of The Twilight Zone. A professor (Sherman Helmsley) trying to solve a mathematical problem accidentally summons the Devil (Ron Glass). The professor is allowed to ask three questions regarding his powers, and then a final question (or task) in exchange for his soul; if the Devil can't do it, the deal is forfeit and he keeps his soul.
 * In Supernatural, Lucifer manages to trap Death into his servitude. Death, who is very annoyed that he's being leashed by a petulant child with daddy issues (...yes, that is how Death perceives the Devil), proves that it's not a good idea to piss off an eternal and infinite force of nature by actually helping them imprison him again.

Music

 * The Devil Went Down to Georgia by The Charlie Daniels Band
 * Though in that case, the Devil was beat fair and square. Johnny is just that good. The golden fiddle was exactly the agreed stake, no tricks.

Mythology

 * The Odyssey: Who has blinded you? 'Nobody'! 'Nobody' has blinded me!
 * Sisyphus from Classical Mythology pulled this off for a little while. He was punished for it, though.
 * A lot of stories involving deals with the Devil have the Devil being tricked out of getting his side of the deal.
 * Jack of the Jack O'Lantern tale in Irish folklore also scammed the Devil. He got the Devil to agree not to take his soul after scamming him twice. When he died, though, he was too wicked for Heaven and the Devil upheld his bargain not to claim his soul. The Devil gave him a glowing coal and wished him the best roaming the Earth. Jack later put the coal in a turnip he carved out and created his lantern.
 * Like many Anglo-Irish folktales, stories about Jack were carried into America's Appalachian region, where they underwent Memetic Mutation. True to form, Scamming Death, the Satan, or The Legions of Hell is a recurring motif, such as the time Jack caught Death in a poke. A Good Ol' Boy defeating cosmic powers through guile may well have resonated with the socioeconomically depressed area.
 * There's a story about little girl sold her soul to the devil for a pail of milk that she spilled. When the devil came to collect she ripped the SOLE off of her shoe, gave it to the devil, then continued skipping along, oblivious to what she just achieved while the devil just stood there dumbfounded at having been tricked by a 7 year old.
 * Many indigenous American trickster figures fall for their own tricks. Of course, it was likely what they wanted to do all along.

Radio

 * That Mitchell and Webb Sound has a skit in which the Devil shows up to claim a man's soul, and he complains that his life of wealth and success had felt rather hollow. Satan gloats that this is what makes it all the more satisfying, until the man reminds Satan that before signing the contract he had asked if he could keep it for a few days, and tells him that he had his lawyer add a clause that prevented the Devil claiming his soul in just such an eventuality which Satan had skimmed over, and furthermore criticizes Satan for running an antiquated operation that clearly hadn't adapted well to widespread literacy.

Tabletop Games

 * In the Dungeons and Dragons optional sourcebook Tome of Magic, one of the vestiges (beings that exist outside of reality) was originally a prolific thief (possibly a kleptomaniac) who, upon his deathbed, renounced all of the theft he had done in life, thus effectively stealing his very soul out of the hands of Olidammara, deity of thieves as a way of proving himself the most worthy of the deity's devotion. Olidammara was pissed at first, but then realised the sheer audacity of his actions and was about to accept him with open arms (and minimal chance of pickpocketing) when the deity realised that accepting his soul in the afterlife would prevent his incredible theft. Since Olidammara didn't want the soul to go to anyone else, the thief's soul ended up outside of all known forms of reality; existing in no plane or identifiable location beyond 'nowhere'.
 * A Dungeons and Dragons character class, the Malconvoker, specializes in summoning evil extraplanar creatures and tricking them into serving good causes. High-level Malconvokers acquire demon lords as their patrons who provide them with great power under the false impression that they're using that power to spread misery and destruction. In reality they're using it to slay monsters and bring down corrupt rulers, making the world a better place on the sly. Needless to say, a successful Malconvoker puts every skill point they can into Bluff...
 * In Legend of the Five Rings, the big bad evil god, Fu Leng, fell to this at the hands of Naseru, who eventually became the Emperor. When Naseru and his siblings led a Big Damn Heroes moment in an attack on Fu Leng's stronghold in the Shadowlands to prevent him from taking over the heavens, while his uber-powered brothers and sister were slaying abominations left and right, Naseru, being a courtier, walked up to Daigotsu, leader of Fu Leng's forces in the material world, and began talking to him. The resulting conversation allowed Naseru to trick Fu Leng into temporarily withdrawing his dependence on Daigotsu, which gave the other gods and dead heroes enough time to take him down and send him back to hell.
 * Eclipse Caste Solars in Exalted have a name for this trope: Tuesday.
 * Marsday, actually.
 * And Fiend Caste Infernals get one additional trick on top of this: they can renege on any promises they make to Eclipses or Moonshadows (the Abyssal mirror of the Eclipses) without suffering any penalties. Yes, that means they can scam the people that scam Cthulhu on a regular basis.
 * The Title Image can be attributed to a plausibly exploitable rule in Warhammer 40000 that may be interpreted so that a certain Ursarkar E. Creed can hide heavy equipment in ridiculously implausible locations due to his Tactical Genius, like building-sized Baneblade tanks behind a lamppost. Thus, culminating in fanfiction and an accompanying picture of him outplaying Tzeentch - Chaos God of Hope, who has also played Gambit Roulette for his entire existance - at chess in a deal that stops Tzeentch from ever interfering with humanity ever again. CREEEED!
 * Or an entire regiment of Kasrkin in the enemy general's bathroom.
 * Or a Titan in a spent firearm shell.
 * Changeling: The Lost features an Entitlement known as the Legates of the Black Apple. When The Fair Folk come barging into the freehold, it's the job of the Legates to try and figure out what they want and how to get them to go away. Mind you, this doesn't necessary involve giving them exactly what they want, and negotiations can involve intimidation just as well as diplomacy. Mind you, being a member of the Entitlement is quite risky -- you don't want to know what the Gentry did to the guy who preferred to use intimidation tactics once they found out his frailty.

Video Games

 * Probably the most clever of them all, Lillet Blan from Grim Grimoire tricks a very powerful demon into
 * In fact, her plot is so impressive that the local would-be Magnificent Bastard Devil Advocat actually backs her on the deal.
 * And to top it all off,
 * While not supernatural beings per se, the Scrin from Command & Conquer are Sufficiently Advanced Aliens with psychic powers and access to exotic, Tiberium-powered technologies. They are led to believe by Kane that the civilisation on Earth has collapsed and that Earth is ripe for Tiberium mining. Not so much. By the time the Scrin realise they've been suckered to landing on Earth, they are already having their asses handed to them by Nod and GDI alike (and the two won't even stop fighting each other to fight the Scrin).
 * Except, it's pretty clear that the Scrin are not the Cthulhu here. It's Kane. Even the Scrin have no idea what he is. And the fact that he hasn't aged since the 40s...
 * The plot of Marvel Ultimate Alliance is essentially Dr. Doom making a Chain of Deals that winds up suckering or screwing over most of the other villains in the universe, including gods like Loki, Mephisto, and Odin.
 * This is the goal of The Emperor in Dissidia Final Fantasy, who plans on living forever and manipulating the gods themselves to become something more than them.
 * In Ever 17, the whole point of
 * In the Dragon Age series, the player can make deals with demons and then back out of them once the demon's brought up their end, often with no consequences worse than having to fight them (which is usually what refusing to deal leads to anyway). In one particularly noteworthy case, you can even trick a demon into teaching you powerful Blood Magic... And then use said Blood Magic to kill the demon.
 * Another notable case occurs in Act 1 of Dragon Age 2, when Hawke can convince an ancient demon to lead you to both . It turns out,   Varric's preferred response? Renege on your deal, kill the demon, and walk away,

Web Comics

 * Order of the Stick: This is Redcloak's ultimate goal, to harness the power of The Snarl and hold the world hostage so he can negotiate with the pantheon of gods to get a better deal for the race of Goblins in-universe, rather than just serving as sources of XP for adventurers.
 * 8-Bit Theater: Thief outsmarting Trickster God Raven.
 * Chicanery begins with Pokey having just embezzled Giygas' $44,000,000 retirement fund.
 * Ayanah in Pawn is implied to be doing this to Baalah, with unfortunate implications.
 * In Sluggy Freelance Aylee comes up with a plan (and Zoë complements it) to trick some nigh-omnipotent Jerkass Genies into granting what seems like a worthless wish (making it rain the blood of the innocent), without them realizing that "the blood of the innocent" is exactly what Torg's Cool Sword needs to become a magical weapon that can kill just about anything, including, that's right, nigh-omnipotent Jerkass Genies.
 * In a parody of Harry Potter and the Chamber of Secrets, Torg outsmarts the pseudo-Literal Genie that's been interpreting people's wishes as "Turn in me into chocolate" (including someone who had merely screamed in terror rather than actually wishing) by wishing that he'd "Turn Torg Potter into chocolate." This results in the kid Torg was a body double for being turned to chocolate, allowing him to safely wish everyone back to normal. (Fortunately, the genie doesn't mess around with the remaining wishes)
 * In Xkcd, Mephistopheles encounters the E.U.L.A.
 * In Homestuck, Terezi . Yes, Terezi managed to manipulate an omniscient being. She is simply the best there is.
 * It's debatable if she really manipulated him, beyond revealing information enabling him to act against a common enemy.
 * Not to mention that the information Terezi gave to scratch was
 * Dominic Deegan had to face The Beast in the Borders of Destruction and he managed to get a Destroyer to take care of The Beast.
 * Later, he runs into the Beast again, and scares it away by pretending to possess the Destroyer's powers.

Web Original

 * Linkara pulled this one off in a big way against "The Entity" in his Electric Tale of Pikachu review.

Western Animation

 * Gargoyles: Xanatos (of course) did this to Puck, when he chose Owen Burnett instead of a wish, forcing Puck to play human for the rest of Xanatos' life.
 * Arguably a bit of a Pet the Dog moment as well. Xanatos could have had any wish he wanted, but passed up a ticket to wealth or power to keep his faithful servant.
 * Xanatos' plan with Thailog goes horribly right when Thailog successfully scams him in a complex "Machiavellian" scheme that Sevarius was sure was Xanatos' idea!
 * The defeat of the Robot Devil in Futurama should be considered partly this, and partly Did You Just Punch Out Cthulhu?.
 * In Metalocalypse, the boys encounter the Devil (well, the Blues Devil) and sell their souls to him for Blues talent. Except they negotiate it all the way down to little more than a $5 Hot Topic giftcard.
 * Oddly, he appears to very reasonably refuse the contract at the time. It's only at the end of the episode that it's revealed that he agreed to these terms -- presumably, he was just that impressed with someone actually managing to put one over on him.
 * Eric Cartman does this LITERALLY in the South Park episodes Mysterion Rises and Coon vs. Coon and Friends as he actually scams Cthulhu into doing his bidding by acting sickening cute.
 * The Grim Adventures of Billy and Mandy's entire premise began with this trope.
 * Vilgax did this to Eldritch Abomination Diagon in the finale of Ben 10: Ultimate Alien. Bonus points for Diagon being actually based on a Great Ancient One.

Real Life

 * The mathematician and strident atheist G. H. Hardy is said to have tried this. Before traveling across the ocean by boat, he sent a postcard claiming to his colleague Littlewood in Cambridge saying that he had proved the Riemann hypothesis. He arrived safely in England at which point he revealed that he hadn't really proved it, and had just blackmailed God by ensuring if the storm had killed him he would have become famous for dying before the proof was known (as Fermat was famous for himself with his last theorem) and thus God would have made His enemy famous.
 * Oddly enough this completely contradicts his atheism since atheists don't believe that God exists. Hardy here claims he knows God exists, but they aren't on the same team.
 * It's called Black Comedy.

"Here comes a pissed-off Eldritch Abomination!"

"Statler: Did you scam a god once?

Waldorf: Yeah. Some feller named Poseidon asked me to get him some ice water.

Statler: So what did you do?

Waldorf: I gave him some ice water. With the ice already melted!

Both: Doh-ho-ho-ho-ho-ho!"