You will mostly watch the MC spectate during the most part of the major plot, but he would not shy away from getting into the mix of things if he has to, which is usually near the end of the arc.

Other than that, he spends most of his time experimenting and making cards. Later on, he starts having some nice moments with his monsters that developed intelligence through his unique methods.

The author still tries to make the MC not too overly OP and he can still improve, even though the attempt is really poor by not really showing how OP others are.

In the current latest raw chapter, 517, he is on summer vacation after finishing his first year.

the pacing is dreadful: nothing happens... And it goes slow, like I would rather be studying kinds of slow...

the guy goes and starts doing some sketchy stuff to avoid becoming the evil god. Nobody bats an eye because of good behaviour. Another fictional universe with brain dead people...

girls fall in love with the dude left, right and centre because he basically ignores them while doing his sketchy stuff

Of course nobody actually interacts with him too much as he is practicing detachment and can’t become too worked up about anything, like a good blank canvas... heck even your average harem MC has more personality than this dude... I never thought I would miss Kirito from SAO...

Tl;dR : waiting for Godot, web novel edition

Dark steals notHarry's potential love interests, memoranda from his family, and makes notHarry almost develop an inferiority complex due to all the public comparisons between them

-Dark created Fusion card but later it was revealed that there are many types of fusion spell so he will have to continue studying in the future if he wants to maybe create Mastermon

-The advance of creating evolved cards of sins that needs studies of ruins and things related to gods to create Sins card to evolve your monsters to new levels
So far the farthest it has come is Pride 4 but it can only be used with certain monsters and it is the only level 4 Sins card but it is still considered defective.

-It is the power of the bonds they have the possibility to replace the sin cards since when pride 4 gatomon is used I need the magic power of dark and its connection to evolve into angewomon

-If this is possible, imagine the reaction of people and your opponent if dark evolving his monster without the need for cards (Removed a great weakness from his deck) or even recreate contact fusion to bring his fusion monster

-Although I hope this only applies to the digimons and not to the other monsters of Dark

-There is also the mention of ritual and another type of summon that has not been mentioned so far so there is still more development for Dark since Blue eyes has good material for summon ritual and and Professor Silver's mention that elves have secret techniques like dual chanted

-In the current chapters it seems that we will see the appearance of other gods since the gods can have influence on the intelligence of creatures such as monsters either from dungeon or dark for which dark could make an advance on the Sins cards or create another God Armed card.

Things not related to duels

-Maybe black clover reference with spirit dive if possible with Dark and the spirit that he gained from Aurora's mother

-Dark won a book to learn fire magic, maybe he can become a magician that his incredible reserves thanks to the power of demon god allow him to destroy someone with magic

-We still don't know everything about alchemy and refinement of armed cards so maybe Dark could in the future do something similar to fullmetal alchemist or Hajime nagumo of arifureta

-Also that chakra or qi thing that is mentioned is the only power of humans than the 7 is considered a new magic imagine if Dark had something like the wortless of DxD or Copy without restrictions (referring to Eeve pokemon with more evolutions or ditto that can be anything)

Dark is becoming an Businessman as he is now laying the foundations for his own company with a focus on the monster duel.

His first Dragon Monster (I don't need to say more)

Have the power of money

The ability to look down on someone and win

Although, unlike Kaiba, he has achieved what he could not, which is to win a tournament that he himself created.

As for Kaito, his resemblance to dark is more in kaito's calmer personality compared to kaiba

-The vision of most of the people of the same year taking him as an omnipotent being instead of a human being who also has defects and weakness

-The brute force of his deck that makes him surpass all his classmate in terms of deck power and his constant growth will leave him alone since he has no one from the same year that he can call a rival so this will produce loneliness and boredom as pandora suffer and told in one of the initial chapters that are translated in novelupdate

(Since dark began to worry about his plays when he returned to face his classmate so that the duel was not so short even though he was able to avoid that mentality he admitted to having lost ability due to being able to depend on raw power)

-Being a noble (This is a possible threat to dark) since dark comes from the modern world I do not think that he is so aware of how to be a noble and how the relationships of the nobility could create rumors against him and attack him just because he does not I worry about it

-The intelligence of his monsters something that Dark himself has questioned since he can only say that time will tell if it was correct to increase the intelligence and independence of the monster from him or no.

only Dianna, Sara, (Eudora we don't know her true capacity), White, Emma

I put Dianna on top of sara because her deck is about power

Sara was able to give dark some true fun back but still failed to face his brute force.
(For yugioh first generation lovers this will surely be a fun duel / chapter to read)

Eudora the power of a possible obsessive yandere has yet to be seen

White and Emma both lost to dark in the silver cup but I see white with more chances because Emma depends on her luck on her deck

Although it will only be possible if dark has an initial bad hand

Now it is under investigation:
Pokemon:
-Virizion because dark got a holy sword with herb and light properties

-Aerodactyl from a biological orb that he obtained in a dungeon

Digimon
-Dianamon (lunamon)

Yugioh (My expectation)
-Replicate his blue eyes custom monster which should be easier since there are more materials but the difficult thing is how to get them and also Dark has to tell the truth to Pandora about what he did with his gift and if dark gets her or Hephaeus give him materials to replicate his blue eyes monster or if these blue eyes custom monster take different routes in the six star but they all become blue-eyes alternate white dragon when entering the 7 stars and then blue eyes white dragon and have the ability to turn into eggs like the first blue eye custom monster.

So we can see how six star monsters based
Blue-Eyes Abyss Dragon
Blue-Eyes Solid Dragon
Dragon Spirit of White
And Dark summon sometime although I think he will need his Sins cards to achieve it and bring Deep-eyes white dragon

Since I really do not want demidevimon to be a monster that has a chance to become the 7 demon lords of digimon since I feel that although it would be important to demonstrate demidevimon as the ace of dark is that I really want to see more demons monster for dark not only for him Problem that someone mentioned in the reviews but I would also like dark to collect or to show moment where he fell into darkness similar to the protagonists yugioh digimon and also to stop dark the appearance of a hero of justice and it will be incredible if in a duel he manages to invoke both belzemon as belphemon rage mode in the field plus another demon lord since it would be incredible although I wonder how author will do it with the pride route

Since I don't like Lucemon and I don't find it interesting compared to Mastermon and since pride 4 seems to lean towards the light maybe the author degrades the form of lucemon: larva mode to make it the same as neodevimon level and the defininitovo level is Lucemon : Satan Mode that would be more original than the male version of Mastermon

Digimon:
Demidevimon
Gatomon
Leomon
Renamon
Agumon

Pokemon:
Eeve
Sylveon
Hawlucha
Honedge
Misdreavus
Munchlax
Applin
Meowth (Alola)
Popplio
miltank
Shuckle
Ditto

Yugioh
Version of blue eyes white dragon
Vampire Fraulein.

Original:
tr*sh slime.
Magic secretary.

The relationship of dark with his spirit is symbiotic and that not only dark affects his monsters but his monster also affects him since Eeve had a talent as a prophet and he developed or awakened this ability in dark that is why dark needs more demon monster since he has 3 monster with the quality of (brave) and only 1 demon monster.

since currently in the raw he 600 and 601 is obviously about the level of anyone from his year and he can no longer enjoy the duel with the people of the same year as now he has started to relax due to his enormous power but I hope he can compose himself as I don't want dark's first real loss in a duel to be because he lost all enthusiasm to fight

Now he's in an internal debate about his plays and I hope Dark can be merciless so he doesn't have to hold back and focus on defeating his enemy no matter how big the difference is.

Hopefully Dianna (For being her friend and having a deck with enough power to connect with dark and motivate him) or Sara (She and her treacherous strategies) can give him back the hope of having a fun duel with people his own age

Dark achieved his dream of obtaining a version of blue-eyes white dragon thanks to Pandora senpai although Dark is scared to tell her the truth about the materials he used since he does not know how she reaction

In his second year, Dark is allowed to obtain another monster as demidevimon and he managed to obtain Agumon and his evolutions through the card pride are related to the digimon route of Agumon from Digimon Squad

The reason why I grouped Dark and white's stag is because the stag saved dark when Lady devimon was corrupted by a mad moon goddess and helped save the life of dark as demidevimon who was in lady devimon at that time.

Just imagine the potential of the stag if dark used his sins cards in the maybe dark would get a version of the pokemon Xerneas when the deer evolved

Reason why white despises and cannot use the potential of the stag.

He hardly ever uses it in his duels

When he drew it, he decided to give up, considering it a useless card, when he faced Diana

First official duel between dark and white

[Mind Light], which can express the power of the soul, once helped him awaken the [Evil Beast] that was corroded by the Moon Goddess.

The upper limit of this nirvana depends on the magister's mental strength, which is a typical psychic ability that will be amplified by the magister's thought and emotions.

As the son of a brave man, if Whitte can make good use of this [soul light] and put his courage into it, he should be able to get good results.

It's a shame that the [Light of Mind] without the magister's spiritual augmentation is just normal nirvana unleashed by magical one-star elves.

This shows that white does not know how to use stag to its full potential.