[quote=@Birdboy]
[@1Charak2] Can I start PMing you these? I feel like a fool in front of these superior duelists.
[/quote]

Gonna be real with you here lad, I'm like 100% of the reason he even spots half the mistakes he does, and doesn't even mention most of the problems I also found with the deck. I also just got the greenlight to share my opinion, so here we go. I'm gonna go down 'em one by one:

-Your first deck was not only *very in-meta* right now, but it also ran a ton of x3 copies (bad) and the unique cards you tried to add actually don't even remotely help the deck's wincon in any way. Its got a one-track, one-mind playstyle that's incredibly boring and wouldn't make for any fun duels.

-Your second deck is a mess. You tried to shoehorn the first deck's gimmick with even more random stuff that didn't help it in any way. You were running 3 different themes throughout (Banish, Archfiend, Control) and that caused it to become aimless and do nothing well. It didn't banish enough nor have any recovery as a banish deck, it ran too little archfiends for an archfiend deck and its control cards (such as the viruses or necrofear) were just too little to appropriately manipulate the gamestate.

-Your third deck has a clear [i]attempted[/i] theme, but its execution is not good. You're running several useless cards (can't summon Overmind Archfiend, the second copy of A Deal with Dark Ruler is useless as you only have one Berserk Dragon, and by removing Emissary of Pandemonium you lock yourself out of being able to summon Chaos King archfiend (A level 7 monster who requires both fiend tuner and non-tuner, which a tribute summoned emissary with a vilepawn was your only way to access, both of which ran at 1, making even the second chaos king in the previous draft of it unsummonable).

But the issues with the third deck don't stop; You're running several cards at x2 for no reason (as there's no reasonable way you'll ever use 2 in a duel), you have no upgrade possibilities (pretty much playing all of the most powerful archfiends already), you aren't committing to generic archfiends or chess (missing stuff like lancer, interceptor, summoned skull vs. half the deck being just chess archfiends, which is missing checkmate) and you're running so many redundant +0 cards (Allure, Terraforming) that don't help you as we can just choose what we draw anyway. Also, Red Dragon Archfiend, while having it in the name, has absolutely *nothing* to do with archfiends. It's very much just a random dragon who had "Daemon" in the name because it was cool. Not only that, but RDA has very much evolved into its own thing over the years, and is most associated with both the "Red" and "Resonator" series of cards.

What I suggest doing is really looking at what everyone else is doing (my current meme deck not withstanding but [url=https://www.duelingbook.com/deck?id=4208655]here's[/url] a link to the actual thing). I admit I'm a bit [i]too[/i] insistent on running cards at only single copies, but that's because there are very few situations in which you want more than 1. Unless it's complete flavor (like the classic triple vanishing lanius opener like Shun) you want as many unique cards in your deck as possible to not only give you more options in freeform dueling, but to make your duels more interesting as well as you can use many more different strategies. Also really think about both your deck's goal and theme and try to be very careful in how you construct that. Both Cosmos and Shiyonichi took the easy way out with archetypes that have a lot of cards, but at least the latter goes for the Emergency Provisions memes. Try to run some obscure cards with "bad" effects too; it's something unique to me mainly, but playing a card like Half Unbreak is infinitely more fun than Waboku, for example. It lends itself better to drama.

TLDR; The more options you leave yourself, the better. Make a deck with a single defined goal, but a lot of ways to get to that goal. What I've been seeing is either aimless or too narrow. Try to avoid multiple copies of cards unless it's absolutely essential or for flavor reasons. Don't run +0 cards unless it has an attached cost you can utilize. Don't mix archetypes.