Hello everyone,
This is one of my favourite decks I've played so far. I've tested a lot of builds, what works for me and what not as much. These are my tips and suggestions for adjustments or improvements for deck depends what you are gonna play against.
Against HERO deck - the biggest problem wasn't really Masked HERO Dark Law but Dark Angel since you are heavy oriented on your Spells. If you going second, just pray they don't have access to D. Angel or just have a way to summon Mirrorjade the Iceblade Dragon and basically waste its effect on it. Also Swap out Mudragon of the Swamp against them. It's useless since Fusion Destiny is a thing and most of your powerful Fusion monsters are Dark type anyways.
Against Floowandereeze deck - effect veiler or impermanence on their first summon should do the trick. If you going first have some negs ready for summons mostly. I would recommend swapping out for Horn of Heaven if you going first (to have at least one more negate).
Against Bystials (even bystials based) deck - x3 Skull Meister if you are scared to run into them, but just 2 is enough for me. 1 in main since I don't like surprises should be enough. Going first is kinda flip, going second should be much better even tho tear/bystials would be a problem in that case.
Against Tear/Ishizu (tear based) deck - Don't go second, and if you do, try to bait their negs on Shrouded Dragon eff or if you already have Branded Fusion then something like Aluber or Fallen of Albaz on summon effs. Just play mindgames. Also, in most cases when you going blind and don't know what you playing against, your Super poly will be useless against it, so if you have BEO3, just swap it out for Necrovalley and Predaplant Triphyoverutum . Necrovalley will hit you too but not as much as them. Yes Triphy is risky and kind of high "cost" but you can easily combo it with either mirror or albion, to clear a board + have a negate either way. Also, activating Necro in first turn after you have your stuff prepared is most-likely to be a GG if they don't have something to clear it up.
Against DWorld/Danger (Apollousa, Bow of the Goddess based too) deck - New DWorld decks are crazy but the biggest problem for you is going second. If you can't negate the right stuff with effect veiler/meister/imperm you are gonna have a big problem or just starting with less than 3 cards in your hand. Also, hitting Dangers in opp hand is crucial so a bit of luck too. And also, pray for no Ceruli, Guru of Dark World . Other than that, the match-up is pretty much coinflip but you can get ahold of it really fast when playing against it. Necrovalley would be a good addition too when having second match.
I do not prefer main-decking Necro especially when I go blind. It backfired couple of times. I've experimented with 3x Branded Opening and Branded in Red as well. I've bricked a lot of times playing it that way, that's why cuting it to 2 was just right imo.
Gold Sarcophagus - my reason to play it, is ofc combo with Tri-Brigade Mercourier -> basically search power, also good bait to negs.
Branded in High Spirits - personally, I do not like playing it more than 1, since it's not really that often when you can actually play it and even if you do, you can bounce it back to the hand afterwards so playing it with more copies would be a waste of space tbh.
Despian Tragedy - 3x is my personal preference. I've experimented with 2x, it works too. You can add one more hand-trap or something else for it if you like.
Ad Libitum of Despia and Dramaturge of Despia - having more than 1 copy of it will brick you for sure. They have awesome effects while used as synchro material - so you basically don't want to see them that often in your hand or even more copies of 'em.
Fallen of Albaz/Albion the Shrouded Dragon - 3x - this is my another personal preference since having "only" 1x Shrouded Dragon, you want to see this guy in your hand basically every turn. I've played with 2 of each but it was kinda lame and coinflip. Ratio 3 - 1 works better for me. Also, you wanna target Branded Sword from your Deck (not hand) with Shrouded Dragon. If you have Branded Sword in hand while using Shrouded Dragon effect I would recommend you to dump Branded Openingfrom your Deck -> most of the times like 95%, you want to draw card not summon S. Dragon. Edit: Added 1x more Shrouded Dragon, since I've decided to play more than 40 card deck.
Super Polymerization - 2x - Yes "only" 2. I found myself bricking on 3x for some reason. Also you are discarding A LOT with this build - that's why having 3x tragedy is a good thing heh. 1 copy of it wasn't really coming in my hand at all when it was really needed. Having bigger chance to have 1 is always good. So 2x is optimal for me. Don't forget to swap it out when going against Tear decks, it will get only negated/shuffled and won't really work against them sadly.
Springans Kitt - 3x is overkill imo. 1x ain't enough, at least not for me. 2x is just right. I mean, you still can play 3x, cut out 1x Tragedy, and try it that way. But with this build, i'm suggesting playing only 2 copies. Edit: Nevermind, 3x is just fine. Playing more than 40 card deck tho. You can still cut it if you want to 2. But I've sided 1x Meister for it.
Artifact Scythe + Back to the Front - The reason playing 1x of both is just to scythe lock your opponent. Since you gonna dump scythe to the grave anyways. Either with discards like Super Poly or with Branded Fusion for Albion. You can basically bait your opponent into Scythe but still having the option of Back to the front is nice. Basically you can use it for bringing back fusions like Mirrorjade so, still win-win situation.
Branded Bond - I was discussing this with few people if this was good or not as main deck card. You won't see this card even in side deck but hear me out. This card came so clutch in a lot of situations. Especially when it can be used for basically Shrouded Dragon from Grave or banished Fallen of Albaz. Even if you summon Aluber the Jester of Despia and they negate his effect you can do some sweet combos with this one card in hand - going for one of those two either from hand/grave/banish - summon it and you have another options from there. This card is so underrated imo, even tho it's pretty lit. Also, one copy is just fine, if you want, you can add 2nd but i am not really sure what you gonna swap it for if you want to keep the cards at 40.
Incredible Ecclesia, the Virtuous - She is incredible! Quite literally. 1x is enough tho. It's cool to have her 2x but, you can recycle her so having more than 1 would be a waste. Also she is "Light" target for your Branded Fusion as well (if you don't want/don't have your scythe in your deck/hand to be dumped) and it's your search card as well.
Hand-traps (Meister, Veiler, Imperm) - 1x meister, 2x veiler - reason for this ratio is my pure preference. Veiler is another "Light" target for b fusion + interupt for field. Meister in other hand can be "Dark" target for fusion as well - looking at the Triphy especially and good grave interupt - but still, only 1 against most of decks is just fine. Having eff negs for field worked much better for me, that's why having 2x imperm going second is kinda clutch as well. Why no Ash Blossom & Joyous Spring? She is "FIRE" - that's mostly why not. Why no D.D. Crow? I mean, you can argue it's better than Skull Meister but he is my prefered card, since he is negating the effect from grave. Why no Ghost Belle & Haunted Mansion? - I'm still thinking of adding her x1, but to be completely honest, I can't see her working in my favor going first, so maybe, just maybe, only 1 copy would be good even if going second. Also - "EARTH" won't benefit any of my fusions at all. Edit: Sided Meister, added Ghost Ogre & Snow Rabbit - Not only hand-trap but "LIGHT" target as well. Also Called by the Grave - i think i don't need to explain this one.
I'll update the list/description if I add/find something new. If you want have some combos explained, feel free to comment it down below, I'll try to add them here in description.
Edit: Added cards to main deck - 1x Branded Retribution
1x Ghost Ogre & Snow Rabbit
1x Called by the Grave
1x Albion the Shrouded Dragon
1x Springans Kitt
Added cards to side deck - 1x Solemn Strike
1x Dark Ruler No More
Moved cards from main to side - 1x Skull Meister
Moved cards from side to main - 1x Branded Retribution
1x Albion the Shrouded Dragon
Removed from both side/main completely - 1x Horn of Heaven (replaced by 1x Solemn Strike )