Woohoo machine deck!
This is a mixed Cyber Dragon list, designed to be capable of breaking boards and OTKing but also very capable of setting up a negate or two, setting backrow, and passing. The idea is you don't know whether you're going first or second game 1, so you tune between games (when you have a guess) and the maindeck tries to balance both.
Into the card by card.
3 Core. Normal Core, add Overflow is a line I actually like in Cyber Dragons. It can also search Cyberdark Realm to open up OTK lines, or summon another 5 to make Infinity. This is just your main starter, and you want to run 3. 3 Emergency, Rota for the deck. Core searches this, this searches Core, pretty basic stuff. The second effect doesn't come up, but mostly because people usually play around it, (and because Ass Blossom works fine) so you're winning on that one anyways. 1 Repair Plant. We're running 1 Kaiju in our boardbreaking suite, but mostly this is just an easy back-up Rota, and it'll allow you to string Rotas. 3 Overflow, best card in the deck. It's an amazing Trap card on its own merits, but it is also insane bait, and I always want to play 3 of this card. 3 Cyber Dragon and 1 Toon. Part of the reason I think this deck is good is that breaking an Elf in the EMZ is easy when you see any Cyber Dragon. These cards are also insane against Machines thanks to Fortress, which isn't huge in the meta, but comes up. 3 Herz. Herz is great to equip to a Regulus, and important to send off of Rampage, and is also just another good Cyber Dragon. Picking itself back up is usually my preferred play to searching Cyber Dragon, but the fact that it recovers itself, or a Core in the GY, or searches Cyber Dragon makes it a great toolbox card. For Cyberdarks I'm on 1 Realm, 1 Chimera, and 1 Power Bond. Power Bond is great to see in this deck, especially going second, and I love the utility of Core + any Spell/Trap equaling popping 2 backrow, picking back up a core, and then OTKing on an empty board. Chimera is weirdly useful on it's own as well, so really you have 3 good cards to add a good engine to Core. I like that. I'm running 1 searchable Cyberload Fusion and 1 Overload Fusion. These cards help push for game by making Rampages, pretty self explanatory. I think Power Bond is actually better than either, and I'm considering cutting either or both of these, but I like running a lot of Cyber Dragon cards in the deck. That's the whole Cyber package.
For Machina cards, it's a pretty simple engine. The real Chad goal is to draw 1 or our 2 Redepoloyments and then use Megaform and Irradiator to summon Citadel. But Citadel can be revived from the GY if Regulus gets popped, or when Irradiator pops itself to summon Megaform. The idea is we have a few brickier cards, but also a lot of chances to put up Citadel while setting up for Regulus and searching Cyber Dragon. It's a 1 card thing that'll break a board pretty easily, though it isn't that helpful against Winda, it's a solid line to save for Splights after pushing through negations. Then we have 2 Regulus, 1 Disco. It's a free extra negate going first, and leads to the potential board of Infinity + Overflow + Regulus + Citadel. Pretty hard to push through that.
For hand traps, my goal was to settle on board breaking cards, but lean heavily on ones that could be set in the even I am going first. So there's 1 Jizikiru. It just makes sense to run in this pile, it's less about searching it and more about a free Kaiju being a early play going second in the deck. 3 Imperm and 3 Droplet - I think these cards are great going first or second, and should contribute to the deck's ability to break boards. I decided to run Lightning Storm over Raigeki or Cosmic in the main. it isn't as good in a grind game, and is outright bad (or at least usually dead) going first, but it flexes as a way to out floodgates while pressuring through (or blowing out_ negations.
Extra deck is mostly about making Rampage and Zeus going second, but Infinity is appealing going first, and it runs a single Durendal, which punishes searches but can also trigger Overflow while negating things, and is pretty good generic negation actually. Lyna is to search Cyber Dragons, Anger Knuckle is a recursive way to pitch cards and threaten Citadels, Sieger mostly enables Rampage plays, but also has a useful battle-protection effect, and Almiraj lets you put Core or Herz into the bin to enable Regulus plays, Repair Plant searches, and many other shenanigans, including their GY effects (though Core will almost always have to wait a turn).
3 Raigeki are super useful for targeting Spright and Tear boards, 3 Cosmic are for Mine and Floodgates, but are also sweet tech cards in a variety of matchups - the effect is deceptively strong if you use your head. After that I felt I was running enough cards to break boards and OTK going second, so the real switchup was going first cards. 3 D Barrier is an insane floodgate effect when you've set up your board, and after that I settled on the Solemn Brigade - Judgment because you need to protect all of your traps, and Strike because the card is also really good when you're going second, because sometimes pushing through and simplifying the game state then setting Overflow can be enough to clear the board once your Counter Trap ends the chain. The basic idea was to be as generic as possible with the blowouts and tech cards, with maybe the exception of the more targeted Raigeki, which is still generically pretty good, especially alongside Lightning Storm.