Nightfall Series: Prince Vladimir laments that his life is boring without a worthy enemy. His solution is to teach The Hero, Myra, how to better manipulate him and how to be a more challenging opponent.
In the Honor Harrington series, Thomas Theisman would qualify, taking into account that Honor fears and respects him at the same time. Lester Tourville, too, particularly after that business in the Selker Rift. And then there's Javier Giscard, Warner Caslet, Eloise Pritchart, Shannon Foraker... Basically, despite the horribleness of the People's Republic's regime, Haven is a hotbed of these for Manticore. Which is why the Mesan Alignment is scared out of its pants when it learns that Manticore and Haven (which has undergone a rather substantial shift in government in the meanwhile) have signed a military alliance.
Victor Cachat and Anton Zilwicki.
In David Gemmell's Ravenheart. One of the Villain's men, Huntsekker, kills one of his own men for breaking a promise made to one of the enemy
When Maurice Le Blanc needed a worthy opponent to his own character, Arsène Lupin, especially as Ganimard simply wasn't cutting it, he instead decided to use Sherlock Holmes, though for copyright reasons, his name was changed to Herlock Shears or Homlock Sholmes (who lives in Parker Street with his roommate Wilson). The first Crossover, where Sherlock Holmes arrives too late, kept the original names, however. Since Holmes became Public Domain, most editions today change it back to the original names.
Also, Sherlock Holmes and Professor Moriarty: at their fateful last encounter, gentleman Moriarty lets Holmes write a farewell letter to Watson before starting their fight to the death, and Holmes knows he can trust Moriarty to wait patiently until the letter is finished and not to push him into the nearby falls while his attention is on the paper.
We have John Clay in The Red-Headed League, who is so hard to catch that he and Holmes never see each other until the story. This trope kicks in near the end-Clay outright praises Holmes for his arrangements and quick thinking, while Holmes compliments Clay for his excellent scheme and how close it came to succeeding. Furthermore, although Clay is outright rude to Inspector Jones, he bows to Holmes and Watson as he heads off to jail.
Later, he comes to regard team leader Jake as such too, repeatedly complimenting his tiger morph. Near the very end of the series, a former hostage of the enemy says they should listen to Jake- a sixteen year old boy- because he's the only person Visser Three is afraid of.
The Sharpe books often included this type of character among the French ranks. Often, the character would be a portrayal of a real French officer whom the author respected. In a military context, this character makes more sense.
In the Aubrey-Maturin books, several French officers (Captain, later Admiral, Christy-Palliere and his nephew, and Admiral de Linois, for example) are this to Jack Aubrey and his men. Also, Captain Lawrence of the U.S.S. Chesapeake.
Sergey Golovko or the Soviet Union as a whole in the Jack Ryan novel series.
In Dan Abnett's Warhammer 40,000Eisenhorn novels, Inquisitor Gregor Eisenhorn regards the Sealed Evil in a Can Pontius Glaw as a being who is intelligent, erudite, charismatic, and likable, and regretfully remarks that if Glaw hadn't chosen to follow Chaos, then they would have been the best of friends.
Rudyard Kipling's The Ballad of East and West is a prolonged exploration of this trope, culminating in the purportedly villainous character being so impressed with his enemy that he sends his own son to serve as the hero's bodyguard.
Kamal has gripped him by the hand and set him upon his feet. “No talk shall be of dogs,” said he, “when wolf and gray wolf meet. May I eat dirt if thou hast hurt of me in deed or breath; What dam of lances brought thee forth to jest at the dawn with Death?”
In his poem "The American Rebellion"Rudyard Kipling wrote of Washington and King Georege's soldiers: "Each for his land, in a fair fight,/Encountered, strove, and died,/And the kindly earth that knows no spite/Covers them side by side."
In Scott's The Talisman, Sir Kenneth and the Saracen.
The titular magicians from Jonathan Strange & Mr Norrell never lose their mutual respect for each other's abilities, even as their rivalry grows more intense.
The Canim from Codex Alera series consider one of these better to have than a friend. Specifically, they have a term for "trusted enemy", which is gadara. To be a gadara is to be highly respected, both as an opponent and a peer; for example, a gadara can enter his own gadara's camp and expect to not be attacked by the guards, as only gadara can spill their blood. Gadara are, however, still technically enemies, just friendly ones. Warmaster Varg considers his own son as gadara to him, and vice versa.
Subverted in The Corellian Trilogy; Han Solo tells his evil cousin, Thrackan, that the Emperor's enemies mourned him as a worthy opponent, though Han knows full well that news of Palpatine's death provoked dancing in the streets.
In the X-Wing Series novel Solo Command, General Han Solo and Admiral Teren Rogriss, respectively the New Republic and Imperial commanders responsible for ending Warlord Zsinj, have a great respect for each others' talents and ethics, seeing their counterpart as an enemy, but a far preferable one to the skilled by cruel Warlord. This extends to a brief sort of truce where Rogriss brings an Interdictor cruiser into battle alongside Solo's fleet in a trap that nearly destroys Zsinj's own flagship. (Since the admiral working with the New Republic in this way is technically treason, Solo arranges for its escort to be composed of captured Star Destroyers so the crew is none the wiser.) The two also share information on Zsinj's tactics, worlds, and holdings—including an extensive corporate empire that funds all of his other projects—that allows their respective intelligence agencies to dismantle his support.
A straight example (also seen in the Video Game section) is seen with the Mandalorians. Much of their history and mentality is in finding worthy challenges and worthy opponents to fight in an inversion of I Fight for the Strongest Side. They don't want to support the strongest faction in the universe, they want to challenge themselves by fighting against it. Unfortunately, this often means challenging the Republic and/or the Jedi (and a Stealth Insult to the Sith, as they aren't the best challenge out there), but the average Mando'ad will often praise Republic soldiers and Jedi for giving them a challenge and fighting with honor.
Ganner Rhysode becomes this to the Yuuzhan Vong during and after his Last Stand in New Jedi Order: Traitor, with the Vong military refusing to use explosives or gas against him in spite of him killing hundreds of their number because it would be dishonorable to deny such a mighty enemy personal combat. After his death, the Vong's martial caste are left in awe and respect of his strength and bravery, and he becomes part of the pantheon of the Jeedai Heresy in the form of the Ganner, an invincible giant with a sword of light who guards the underworld's gates. Said gates are inscribed in Basic, not Yuuzhan Vong, with Ganner's battle cry: NONE SHALL PASS.
In Dark Lord—The Rise of Darth Vader, Roan Shryne and Darth Vader come to see each other as this. On Vader's side, this seems to be because Shryne reminds him of the Jedi he used to be, and he considers killing Shryne to have brought him closer to the dark side. When they finally duel, they are evenly matched in swordsmanship, and Vader only wins by withdrawing and using telekinesis to throw a storm of planks and splinters at Shryne.
Jelaudin in Bones of the Hills—having survived the fall of Samarkand, he understands the Mongols' tactics and is able to counter them. Genghis Khan privately admits a grudging respect for him. Just to drive the point home, his life after the loss of Samarkand is a compressed repeat of Genghis' own. When he dies, Genghis himself comments on his courage and honour.
Rana Sanga in the Belisarius Series is the Worthy Opponent to Belisarius as a general, and to Raghunath Rao and Valentinian in individual combat. He has the latter healed and treats him as an honored guest after (just barely) defeating him in single combat and taking him prisoner; when Sanga's army is forced to retreat from the invasion of Persia, he releases Valentinian. In the last two books, Valentinian's role in protecting Sanga's wife and children from a plot against them by Link and the Malwa dynasty is key to Sanga's Heel Face Turn, and he eventually sends his own son and heir to be Valentinian's apprentice in the art of combat.
Also, Domodara, to a lesser extent, and before theirHeel Face Turns, Kungas and Vasudeva. In fact, the Rajputs and the Kushans in general, being Proud Warrior Races, kind of qualify for this.
In The Mists of Avalon, Uther Pendragon cries because the death of a viking king he slew, calling him a good enemy.
Lancer and Saber in Fate/Zero. Neither one is really a bad or good guy, they just happen to be on opposite sides pursuing the same goal. And their Masters are both a lot less noble.
Another example would be Rider and Archer. While Rider is generally affable and respectful against everyone (including the aforementioned Lancer and Saber) unless they show themselves as despicable, Archer is an incredible elitist who considers Rider one of the only beings in the world worth actually respecting. They consider each other worthy opponents to the point that before their final clash, they stop to finish their wine and have one last conversation before each casually walks to the starting positions of the duel.
Emeth, the good Calormene from C. S. Lewis's The Last Battle, tells Peter that he'd be glad to have him either for an enemy or for a friend, and that there's a Calormene poet who wrote, "A noble friend is the best gift and a noble enemy the next best." (Possibly, he sought to invoke a legend about the Real Life Muslim conqueror Saladin, who was famous for his "noble" treatment of Christian enemies.)
Harry Dresden and Gentleman Johnny Marcone seem to invoke this trope even though they seem to end up working together more often than not. Both mistrust yet respect the other's accomplishments. Marcone seems to always keep his word and, in Small Favor, refused to be rescued before the twelve-year-old Archive. Also, when Harry finds out about the comatose girl, he tells Marcone that he can keep the Shroud of Turin for three days as long as he mails it back afterward.
Harry also earned this status with the Erlking, Faerie Lord of goblins and master of The Wild Hunt. He initially pissed off the Erlking by trying to bind him in place to save the world (long story, involving ghosts, ghouls, necromancers, and a couple of very important books) and the Erlking intended to kill Harry for the offense, but then Harry raised a freaking T. rex zombie and rode it to war, which impressed the Erlking so much that he put off the impending wizard-killing until their next meeting. When they do meet again, the Erlking sarcastically refers to Harry as a "guest" and Harry latches onto that like a bulldog, further impressing the Erlking with his quick mind and Politeness Judo.
Subverted with Paolo Ortega. When he attempts to resolve the conflict between the White Council and Red Court with a Trial by Combat between Harry and himself, Harry is initially impressed by his seeming desire to end the war with as little bloodshed as possible. However, other characters warn Harry that vampires don't live to be Ortega's age by acting honorably, and if Ortega's playing nice, it's only because it suits his purposes to do so. Sure enough, it's later revealed that Ortega has ulterior motives in wanting to end the war, and when Harry gets the upper hand during their duel, he immediately throws his façade out the window and cheats.
Varr in Ben Counter's Warhammer 40,000 novel Chapter War. When he learns that the Soul Drinkers are renegades, he admits to being in a penal unit for having revolted, for much the same reasons. He does not fight them until compelled by the Howling Griffons, and apologizes for it.
Rizzett: You know, if the Tyranni were all like him, damned if I wouldn't join their fleet.
Isaac Asimov's Foundation has at least three Worthy Opponents. Two are individuals: Bel Riose, general for the doomed Empire, and the magnificent Mule. Both fight honorably, respect their opponent (the Foundation itself, rather than any one individual), and are honestly trying to do their best to improve conditions for everyone in the Galaxy. The third is the Second Foundation. The two Foundations are both mirrors and inversions for each other. They function as allies and rivals, and the relationship changes a great deal over the course of several books.
The Earl of Thirsk is regarded by the protagonists in Safehold to be the single most dangerous commander the enemy has. Given that he was able to score the first victories against the otherwise Curb Stomping Imperial Charisian Navy, this assessment is completely justified.
The earl's Kingdom of Dohlar as a whole reaches this status as the war with the Temple goes on. Aside from the general competence of commanders like the Earl of Thirsk, the soldiers themselves continued to fight against the Charisian forces despite ever decreasing odds of victory and are easily the most successful military force fighting them. They also commit few, if any atrocities on their own. The kingdom's single worst act, handing Charisian POWs to the Inquisition for Cold-Blooded Torture and execution, was forced on them. When the war ends there are few hard feelings between Charis and Dohlar as a whole, with Charisian businesses seeking investment opportunities in the kingdom within months of the initial ceasefire.
In the Iron Man 2 novelisation, Tony eventually admits to seeing Ivan this way.
Given that it's set in a war-torn universe with prominent Humongous Mecha, BattleTech fiction features these every so often, with perhaps the most iconic example being the rivalry between Morgan Kell (honorable mercenary) and Yorinaga Kurita (classic samurai and follower of bushido) that forms one of the plotlines in the Warrior trilogy.
The Science Fiction and Fantasy of Poul Anderson are full of worthy opponents; in fact, the opponents in most of his works fit into this type. For example, in the novel Star Fox, a relationship of grudging respect is built up between the hero, space privateer Gunnar Heim, and his enemy, Cynbe, an exceptionally gifted member of the alien Alerione, trained from a young age to understand his species' human enemies to the point of being alienated from his own kind. In the final scene, Cynbe challenges Heim to a space battle which only one of them would survive. Heim accepts, whereupon Cynbe says, "I thank you, my brother."
Captain Marco Ramius and the titular submarine to Captain Bart Mancuso and the USS Dallas in The Hunt for Red October. The two actually ally and help command the same submarine in the later book The Cardinal of the Kremlin several years after the former's defection.
Frederick Forsyth's The Day of the Jackal relates the battle of wits between the Jackal (Chacal in French) — an assassin hired to kill French President Charles De Gaulle — and Deputy Commissioner Claude LeBel of the French police, charged with stopping him. Lebel and the Jackal develop a grudging respect for each other, without ever meeting — with the Jackal again and again evading Lebel's clever traps and Lebel again and again penetrating the Jackal's clever disguises. Lebel certainly appreciates the Jackal far higher then he does the government officials he has to work with. When they at last meet face to face, they look, for a split second, into each other's eyes, Lebel saying "Chacal" and the Jackal saying "Lebel" before they scramble to kill each other. Lebel, being a split second quicker, wins. On the following day, he attends the Jackal's burial in a nameless grave, saying nothing to the handful of other people present.
Ned Stark felt this way about the Kingsguard he and his companions had to slay in A Song of Ice and Fire. One particular instance that highlights this is when Ned makes it a point to return Arthur Dayne's sword, Dawn, back to his family.
Martel is portrayed this way in The Elenium, despite his betrayal of the Pandion Knights. Before the final duel, he expresses a similar sentiment about Kurik. When Martel is killed, Sparhawk and Sephrenia both mourn over him, and Martel calls them "the only two people that I ever loved"
Erich Von Stalhein in the Biggles books is of a similar mould. A clear-cut case of My Country, Right or Wrong with a stubborn sense of honour and no particular loyalty to any of the regimes he serves under, except perhaps Imperial Germany, he eventually ends up betrayed and imprisoned by his Soviet superiors in East Germany and imprisoned on Sakhali precisely because of this trope.
The Norwegian detective Harry Hole and Rudolf Asayev, the urbane, intellectual and utterly ruthless drug lord Hole confronts in "Phantom", the ninth book of the series. When Hole finally unmasks Asayev and they come face to face, Asayev congratulates Hole for the ingenious way Hole escaped the fiendish trap which Asayev had set for him an hour earlier, and says "I really like you, Harry, what I heard of you was not exaggerated". The two then engage in a long philosophical conversation, discuss the moral merits of drug-pushing vs. police work and the complicated relations both of them have with their respective sons, and Asayev tells Hole quite a bit of his life story - and all while talking, both of them prepare their hidden weapons and get ready to kill the other one by surprise. The confrontation, when it comes, ends with Asayev severely wounded and Hole in possession of Asayev's knife - whereupon Asayev whispers: "The iron. Bless me with my iron, my boy. It's burning. For both of our sakes, bring this to an end." Harry Hole, however, cannot bring himself to kill Asayev. Only when Asayev provokes Harry beyond measure by threatening to kill Harry's son by slow torture does he do it.
British statesman Lord Chesterfield regarded the Jesuits as the "most able and best governed society in the world." in Letters to His Son (letter 85).
This is how the Nadir ruler Ulric views Druss the Legend, Deathwalker, in Legend by David Gemmell. When Druss falls, Ulric gives him an epic funeral pyre, and honourably accepts some of Druss's allies on the walls to the ceremony.
Supervillains are careful to cultivate this reputation with superheroes. That way, when they inevitably retire, they'll be treated well instead of hunted down in revenge. Villains who get too violent (especially against children) find themselves fighting Mourning Dove, who is notoriously bad at bringing in opponents alive.
At the end, Spider apologizes to Penny for treating the Inscrutable Machine like children, and congratulates them on foiling her plans. Sure, she still got what she wanted, but that was just luck.
In D.K. Broster's historical novel "Flight of the Heron", set during the Jacobite rebellion of 1745, the Scottish Highlander rebel Ewen Cameron and the British Army officer Keith Wyndham constantly fight each other, repeatedly capture each other - and repeatedly save each other's life.
Lensman: Helmuth of Boskone is this for Kimball Kinnison. Two novels after Kinnison kills Helmuth, Kinnison looks at a Boskonian defensive emplacement and his first reaction is "Helmuth would never have been this sloppy".
In People of the Wind Ythrians and Terrans are worthy opponents of each other, and in the Flandry era of the Technic History series several Meresians are as well. In this series and elsewhere Poul Anderson tends to prefer that the antigonist side has at least one admirable person on it, even if sympathy on the whole is a blatantly against them.
In Insurgent, Tris might be the enemy, but the Dauntless will still honor her for walking to her execution.
Generation Kill: Several members of the Iraqi armed forces become this to the protagonists, whom at first are dismissive of the Iraqi military. Espera openly praises the discipline of a Republican Guard who died with his finger on the trigger. In one instance, the Marines take an Iraqi soldier prisoner, and are immensely angry with him for resisting them, but when they realise he has similar standing orders to theirs, and has followed them in a way any of them would be proud of, they immediately start giving him candy and cigarettes.
Foxface from The Hunger Games. In the book, Katniss is constantly shown to respect Foxface and admire her tactics, often wishing she'd thought of them herself.
So 'ere's to you, Fuzzy-Wuzzy, at your 'ome in the Soudan;
You're a pore benighted 'eathen but a first-class fightin' man....
In the Vlad Taltos novels chronologically after Phoenix, Vlad develops this relationship with Jhereg noble called the Demon. As one of the leaders of the Jhereg Organization, the Demon is obligated to have Vlad killed for breaking the rules of the Organization and testifying to the Empire. He also makes it very clear that it's nothing personal and deeply respects Vlad's cunning and skills, saying that he would have liked to have Vlad as a subordinate. For his part, Vlad respects the Demon's intelligence and pragmatism and admits he would have liked to work under the Demon.
In Bernard Newman's Second World War thriller Maginot Line Murder the idiosyncratic French detective Papa Pontivy and his British partner (the writer's namesake) are confronted with a mutilated corpse found in a fortress of the Maginot Line in the tense time of July 1939, just prior to the outbreak of war. With virtually no shred of proof, Pontivy follows his hunch - that a French officer with a seemingly impeccable record is in fact a German spy, who had committed the murder in order to protect his secret. Gradually Pontivy and Newman do find pieces of evidence pointing to a highly resourceful spy, whose true name was Schmidt, who originally enlisted in the French Foreign Legion, took the identity of a French officer killed while on colonial duty in Morocco, came to Metropolitan France and gained an appointment to the sensitive Maginot Line - there to start a major espionage and sabotage network. The more Pontivy and Newman discover of him, the greater their respect and indeed admiration for a man who was able to carry out to perfection such an elaborate masquerade over years upon years, alone among his country's enemies. This is reflected in the dialogue when they finally come to arrest him. "What can I say? You won, Monsieur Pontivy. Take me, I have to pay for my failure. But don't hold me in contempt. All that I did, I did for my country". "I don't contempt you, I admire your courage. That is why I came to arrest you in person. (...) I am not too happy about this business. You are too good for the guillotine. You have served your country with great courage, it is not your fault that you failed. I can't regard you as a common murderer." - "Thank you". -" I have here your pistol, with a single bullet in the chamber. If you want, we can go out and leave you alone in this room". - "I am not afraid, but it is sad to die alone. I don't suppose you would want to shake the hand of a German spy?" - "I would not shake the hand of a German spy, but gladly would I shake the hand of a brave man!" Pontivy and Newman shake the doomed man's hand and leave. When the fatal shot rings out, the tough Pontivy wipes a tear, muttering "There goes a man! I wish we could have let him escape...". Adding to the story's poignant end is the fact that a few months after it was published in London, Germany launched its great armored offensive, effortlessly bypassing the supposedly impregnable Maginot Line and occupying France. Thus, the present-day reader knows that but for Pontivy's gallant gesture, the spy Schmidt would have spent a few months in a French prison and then been liberated by his country's army in June 1940.
Conan the Barbarian and his arch-enemy, the mighty wizard Thoth-Amon. In "Shadows in the Skull", forty years of bitter enmity and a chase half across the world culminate with Conan (and his son Conn) killing Thoth-Amon on the shore of what would become the Indian Ocean. Afterwards, Conan muses "He was the greatest of all the foes I have overcome. I shall miss the old scoundrel, in a way". It is worth noting that in the original Robert E. Howard Conan stories, he and Thoth-Amon were no foes at all. They occasionally run across each other, each having his own separate agenda, and in some cases even did each other an unintended good turn. It was only the later continuators of the Conan saga, Lin Carter and L. Sprague de Camp, who felt that the original Conan lacked an arch-enemy and that Thoth-Amon would fit the role.
In Wolf Hall, Thomas Cromwell genuinely likes and respects Catharine of Aragon and her daughter Mary for their refusal to slink away quietly when Henry VIII throws them over for Anne Boleyn, even though Cromwell is the one who made it possible for Henry to do that and Catherine's recalcitrance the source of many ongoing problems with Europe. (According to the writing Eustache Chapuys left, the real Cromwell did say that Catherine would have rivaled the great heroes if she'd been a man.)
In Worm, the Endbringers - a set of Nigh InvulnerableKaiju monsters who have been regularly attacking humankind for thirty years by the start of the series - are implied to be created specifically to act like these for Eidolon by his powers. In this case, the revelation that this is happening stuns the Chronic Hero Syndrome Eidolon so badly that he falls into a Heroic B.S.O.D..
In Twig, the protagonist, Sylvester, experiences moments of great excitement whenever he encounters someone that could rival him as The Social Expert, because simply to watch what they do in response to his own moves is completely fascinating. He finds two in the form of Reverend Mauer, a charismatic religious leader who stages a populist uprising, and Genevieve Fray, a rogue Mad Scientist with Super Intelligence which has allowed her to optimize her brain for strategic planning and politics.
The Stormlight Archive: Eshonai, the Parshendi general, views the Alethi Highprince Dalinar as this. When he escapes a horrible trap by the skin of his teeth, she allows him and his army to rest within arrow range of her army without attacking. When things start getting really desperate, she requests a meeting with him to find a way to solve things peacefully. Unfortunately, she gets possessed by a Voidspren, so the meeting ends up fruitless.
In post-apocalyptic Victoria, Hauptsturmfuehrer Halsing of the neo-Nazi Landwehr proves to be this in his interactions with protagonist John Rumford. While Rumford and the rest of the Northern Confederation quite despise the Nazi ideology, Halsing's resourcefulness, erudition, politeness and unselfish devotion to his cause earn him their grudging respect when they capture him. He seemingly reciprocates the feeling after escaping.
Rumford: About three months later, I got a nice letter from Captain Halsing, postmarked Milwaukee, thanking me for my hospitality. He was the model Nazi, cold, competent, and perfectly polite.