Yu☆Gi☆Oh!

The Yu-Gi-Oh! franchise is today strongly associated with the eponymous card game, but early in the manga it contained a dazzling variety of high-stakes, often life-or-death games, and the first anime adapts this portion of the series. If one is drawn to NGNL for the concept of betting everything on a game - any game - one will find it echoed here. In a way, however, the two stories are flipped around; Sora eschews magic, battles against magical cheats, and struggles against magical foes, while the spirit of the Millennium Puzzle (although certainly hating when his opponent cheats) is more than willing to cheat with magic or use it to punish even a non-magical loser. read more 

Both series involve high stakes gambling and unorthodox game playing, with the use of psychological strategy. Both series also contain the use of a similar psychological battle game: E-Card from Kaiji is extremely similar to Raijinhai in Yu-Gi-Oh!  

The main characters love puzzles and are challenged by different people in an episodic fashion. In both series, the protagonist receives an ancient artifact that in a way takes over their mind and solves the puzzle for them (not so much in Kami no Puzzle as the artifact awakens the boy's true power, whereas Yugi actually becomes possessed by the spirit). In both series, the characters risk their lives in solving puzzles. It also has a mention of Egypt and pyramids and how the puzzles began there, which is another factor present in both. I would also recommend YGO Duel Monsters (original Japanese of course) as it has the theme of protagonists being lured into some shady competition against their will. But all in all, this first YGO series is more similar to Kami no Puzzle (and also focuses on various games, unlike Duel Monsters which focuses on just that), though certainly has a much darker and creepier atmosphere.  read more 

Both feature different games that involve punishments for the loser. Yugioh Season 0 is less gruesome, but both have a high tense atmosphere. 

in this shonen anime there are no duel monsters but there are yukai and the hero has two personalities just like yugi while the heroine reminded me alot of anzu..thank god there is no seto kaiba replacement here!! 

Both focus on dual lives as well as also magical objects and also rivarly between players in respective professions as well too. 

both focus on suspense elements as well as the concept of unique games each episode as well too. 

Both have a focus on friendship, a young mc that has been through a lot in the story and also elements of supernatural as well too from someone older than they are. 

They have realistic stories but with a supernatural element. Both are presented in an episodic fashion where there's a character that mentally tortures cheaters and wrongdoers in general, giving them a "taste of their own medicine".  

Duel masters is pretty much a Yu-Gi-Oh rip-off - trading card game popular among kids, and the anime portrays it as capable of materializing the monsters portrayed on the cards. 

Both have a main character who has a consistent (or at least mostly consistent) power, uses it to solve problems. A few episodes in the franchise are almost literally the same as Yu-Gi-Oh! "Season Zero". 

Both Yuugi and Niwa have another soul in their body, and have a friend with the same thing. The main girls are similar in their characters and even look the same: Risa = Miho (moments with Risa and Niwa are very similar to moments with Honda and Miho), and Riku = Anzu. 

Both stories feature normie characters getting caught up in strange events one day as well as also friendships with people they would not expect and also unusual artstyles that are very eyepleaseing to look at. 

Both are focused on psychological and suspense elements in it as well as lots of twist and turns and bad shit happening when they least expect it as well as also nice art and character designs too. 

Both have lots of mythology based creatures,and special devices to summon them as well as also a high stakes play or lose really badly scenario as well too. 

Both have a dual sided mc,lots of suspense,occultic,psyhological and elements of horror in it and also stopping bad guys as well too. 

both are action themed anime with a supernatural twist with them nice art and character designs as well as suspense too also double identity stuff as well included.  

both series have creative character designs as well as a dark suspenseful supernatural themed plot as well too with lots of messed up shit happening too. 

both are focused on friendship and and lots of nice to look at art and visuals as well too and are also focused on a particular rival game against each other as well too. 

Both are duel themed battle anime with a focus on using a form of sport as a way to combat as well as also fighting against the badguys and making friends along the way stuff too. 

Heck of a reach i know lol, but aside from the obvious being both having young blonde leads and assisted by a older spirtual like being for their goals and of course the friends they make along the way and catchy music too. 

Both focus on supernatural storytelling, a spooky atmosphere, a young adult cast and also lots of action in it as well too and also supernatural creature summoning included. And a ya cast and their dark sides too.  

Both being based around suspense and dark storytelling as well as characters with different sides to them specially darker ones like the mc being troubled due his nature as well too and also nice art and character designs too. 

both are duel action themed anime with a supernatural twist with them nice art and character designs as well as suspense too. And also an mc having a dark side as well too and some horror elements included.  

Both have an outcast mc in it as well as a focus on deadly games in it as well too where the player must win or else suffer the consequences. 

both are focused on outsider mcs standing up to evil people with supernatural ways and it also focuses on creepy monster designs as well too and also both sharing a school setting as well too. 

both are dark toned series that focuses on a lot of supernatural shit and mythos as well too and also messed up looking demon designs and nice looking art and visuals as well too. 

Both are based around occultic supernatural storytelling as well as lots of suspense and psychological shit happening as the story goes on as well as the characters getting caught up in some strange events as well too.  

both are focused on puzzle solving as well as alot of supernatural stuff as well too. 

They are both the same of the genre both souls have the same or similar story both main characters have never lost even a passion at cards and both have a rival who want to save their family or sister or brother, and have friends who follow everywhere. 

Trading card game, protagonist with crazy hair, materializing card monsters, kids demographic, Dual Masters is basically a YuGiOh rip-off. 

Both shows feature young heroes as well as uniquely designed monsters. Both have strong themes of friendship as well varying puzzles and obstacles for our heroes to overcome. 

Dual identity themes,dealing justice to bad guys as well as lot of supernatural shit in it as well too and nice to look at art and interesting character designs.  

both focus on a young cast as well as both having a dark setting in it as well too with lots of messed up stuff happening and tons of suspense too. 

Both have a character thats willing to commit dark acts and occultic stuff in it too and a dark and edgy kind of feel to it. 

Both are based around occultic supernatural storytelling as well as lots of suspense and psychological shit happening as the story goes on as well as the characters getting caught up in some strange events as well too. 

Both stories have quite a bit of suspense and horror occultic elements in it and are focused around punishing evil people in karmic ways. 

both are based around mythos and punishing the bad guys and duel identities as well too. 

Majin Tantei Nougami Neuro and Yu-Gi-Oh! (Toei version) are similar in several ways. They are both Shonen Jump series. They are both highly episodic but have extended arcs in similar places (Shadi-Aya, KaibaLand-HAL and MonsterWorld-South America).They both involve someone punishing wrongdoers with the help of mental torture. They both have a recurring villain (Kaiba-X) who wants to beat the protaganists. They both have a cast of eccentric characters and one-shot villains. Both series have a case with a serial bomber. Yu-Gi-Oh however has less death and a larger emphasis on friendship, while Neuro has more shock value and is focused more on the villain's psychology. 

Both feature characters who lead double lives to punish the bad guy and no one suspecting the person that is least expected is actually the alter ego that they potray too.