The King of Games is not just a gamer, they are the gamer. In this world they live in, all games, be they video, tabletop, card, are their playthings. Alternatively, if there is just one game central to the medium in which you encounter them, they will specialize in it. Either way, they are masters of the game, stunning onlookers with their prowess and achieving feats of gameplay thought impossible. They have the highest score on the board, the best record time, the best built deck. In short, when it comes to their game(s) of choice, they are the best.
In any work where this trope is at play, expect Serious Business and The Rival to come up more likely than not. If you're playing a video game where you have to face this character, expect to find out that The Computer Is a Cheating Bastard.
Compare World's Best Warrior, if the game is on a large and destructive scale. See also To Be a Master, if a character's goal is to become this trope, UltimateGamer386, when a plot focuses on this trope in regards to an MMO game, and Godlike Gamer, which becomes this for video games.
- Yu-Gi-Oh! is the Trope Namer — Yu-Gi-Oh is Japanese for "King of Games" or "Game King". In the original manga, the story was not focused on Duel Monsters, but on games in general, and Yugi Mutou/Dark Yugi ("Guardian of the Shadow Games") was able to master all of them (in fact, his name, "yugi" means "game"). At least once or twice, antagonists wanted to defeat him and claim the Millennium Puzzle to become the new King of Games and/or Guardian of the Shadow Games, such as in the Dragons Dice & Dungeons arc. Dark Yugi especially since he almost never loses a fair game until the normal Yugi beats him at Duel Monsters at the end of the series, which is what finally allows him to pass on. Ryou Bakura/Dark Bakura is also an expert at games, but they specialize specifically in Tabletop Role Playing Games. Seto Kaiba also has a reputation as a top gamer, including having his name on top of the scoreboard of every game at the local arcade, though this mostly falls by the wayside after Yugi beats him a couple times.
- In the 4Kids dubbed anime, Yugi wins this actual title in Duelist Kingdom (in the Japanese version and the manga, it's the "Duel King" title), and becomes known as the greatest duelist in history decades into the future. Numerous other duelists throughout the franchise, particularly the main protagonist of each spin-off, also become famous as dueling legends.
- Actually Yugi & Yami Yugi aren't the only protagonist to hold the title. As said above the title King of Games is "Duel King" in the manga/Japanese Dub. Fast forward 2 series later Yusei Fudo becomes the King of Games after defeating his rival/reigning champion JACK ATLAS pretty early on in the series and maintains that title throughout the series. In fact the final villain of 5Ds Z-ONE implies that in his time (200 years into the future) Yusei may've actually reached Yugi's level and surpassed with him with multiple duelist in the proceeding generations were inspired by him, strived to be like him, and regularly talked about him for his heroics.
- Fast forward another 2 series later and Yuya Sakaki is crowned King of Games after defeating JACK ATLAS in the Friendship Cup. Meaning 4 other characters aside from Yugi/Yami Yugi have achieved that title with 2 of them being fellow main protagonist. Ironically Yugi, Yami Yugi, Yusei, and Yuya have won the title and none of them even cared about said title in the first place opposed to Judai/Jaden Yuki and Yuma Tsukumo who wanted that title and worked all of their series for it but never won it all.
- Kirito from Sword Art Online technically counts, though it doesn't really come off as this given that the "games" in question are virtual reality MMORPGs. That said, he still is pretty much the best VR gamer in the world.
- Keima from The World God Only Knows is the opposite of Chiaki, being the reigning "god" of dating sims. This becomes important when escaped spirits can only be captured by use of the skills he's learned from gal games.
- Parodied in Ranma ½ with the Gambling King who is actually terrible at games and can only beat young children, unfortunately Ranma is even worse.
- In No Game No Life, Tet is the benevolent gamer God of Disboard, a world that revolves around games. Naturally, Tet is the best gamer in the world and can only be challenged by someone who conquers all the races of Disboard. There is also Sora and Shiro of the BrotherSister Team known as "『 』". They are expert gamers from Earth and it's because of their skills that Tet found them Worthy Opponents and brought them to Disboard.
- The minor Superman foe The Puzzler was highly skilled in parlor games and puzzles, and was a champion in multiple card games. His first crime spree occurred when he attempted to murder a group of people, each of whom had beaten him at a particular card game.
- In The Player of Games, Jernau Morat Gurgeh is so famous as a gamer that he is selected to play the game of Azad in the Empire of Azad as part of a Culture plot to destabilize the Empire's government.
- In the Apprentice Adept series, Stile is an expert at many games, and participates in competitions where each player chooses an aspect of the game to be played.
- Ready Player One features the creator of OASIS, the virtual reality world, James Holliday. James Holliday's challenge reveals that there are many players who are masters of games, but the three main players are the protagonist, Parzival, his friend, Aech, and Art3mis. At the end Parzival becomes the new grander King of games.
- Little Myth Marker introduces the Sen-Sen Ante Kid, greatest player of Dragon Poker in any universe. Naturally, Skeeve winds up having to play against him.
- Marshall Eriksen is this in How I Met Your Mother. While watching Barney play a game of xíng háishì bùxíng he picks up on the rules almost immediately, predicts a yet unseen bonus round and gives Barney advice on how to win the game. After watching two rounds. Played in Chinese. He is so good at games that the others don't let him play any game with them anymore, and he instead runs the game nights.
- Barney himself is this in the world of The Price is Right. He easily wins every game throughout the show without even trying. He even used 29 seconds of his 30-second timer to show photos of himself to Bob Barker. Because he's Barney's father.
- Emu's gaming persona M in Kamen Rider Ex-Aid has quite a reputation in the gaming community, with many characters calling him a genius gamer (to the point that "The Genius Gamer, M" is a Share Phrase used to describe him by pretty much everyone.) This is why CR went looking for him in the first place; they have doctors who know what they're doing medically, but they needed someone who knew the gaming side of things.
- Final Fantasy VIII makes Triple Triad a sidequest, with Balamb Garden having a club of elite players to challenge, leading up to the Card King, their best member. There's also the Queen of Cards, who travels the world manipulating card rules and allowing you to win rare cards from her if you can figure out how.
- Final Fantasy IX has the card game Tetra Master, of which Cid Fabool is the champion in Treno, and is famous for using only oglop cards.
- Fallout: New Vegas has the card game Caravan. Ambassador Crocker is the richest player of the game in the Wasteland, putting up thousands of caps a game, and he's good at it to boot. Surprisingly, No-Bark Noonan is also good at the game and as rich as Crocker when it comes to wagers.
- Kamek as the elusive "Game Mage" in Mario Party Advance.
- Celestia Ludenberg in Danganronpa: Trigger Happy Havoc is regarded as "The Ultimate Gambler," renowned for making her living in the arena of underground gambling while still in high school, who claims to have never lost a game in her life (it holds up; every time the player challengers her at something relating to games, she wins handily). Her knowledge of game theory and the psychology of play (along with her sheer cunning and manipulative nature) earn her a secondary nickname outside the school, "The Queen of Liars."
- Chiaki Nanami, the Super High-School Level Gamer from Danganronpa 2: Goodbye Despair. The only genre she's bad at is Dating Sims.
- Captain N: The Game Master, the titular hero is this trope, which is why he was pulled into Videoland to help them fight Mother Brain.
- The episode "Guitar-Queero" of South Park centers on Stan and Kyle becoming masters at Guitar Hero. The episode also features Thad, who is so good at the game he can play it from memory, miming button presses just with the name of the song.
- The Master Of Games in Teen Titans is a look at this archetype from a sporting/competitive perspective. He's not really all that powerful/capable as far as his own contest is concerned, but he's still hugely obsessed with victory above all else, making his title more of a description of his ability to organize games. He ends up being more similar to Amazo than anyone else, for the simple fact that he ultimately uses the contest as a front to steal powers.