Diaboromon is one of my favorite Digimon ever since childhood, and finally I could say the deck is actually really good, and this is the decklist I've been testing in the Project Drasil, let's see the card by card.
First talking about the Digi-Egg, BT2-006 Tsumemon still is my favorite black Digi-Egg for Diaboromon, because the +2000 DP can save your Diaboro from some checks in security like Heaven's Judgement, and remember EX6 Diaboro don't give Jamming to itself, so having 13k DP can save your best card.
After that the Level 3, first the one I aways prefer to have in my evolution stack: BT2 Keramon, with the weakest setup you can draw basically two cards just for evolving into your Diaboro (one for rules, the other from its inherit), and it snowballs like crazy if you have an Arata in the field or you can make another Diaboromon, just fantastic.
EX6 Keramon is your best searcher, because even though it only reveals 3 cards, it trashes the other ones, and that will be extremelly important for other cards in the decklist, and its inherit is kinda good too, tokens are always good in this deck.
And finally the BT5 Keramon, I really don't like that one but I feel like I have to use it, because its the only other searcher the deck have and it reveals 5 cards, I hope we get something better in the near future (please make the Cyber Sleuth Support set real).
Now the Level 4, well starting with the BT2 Kurisarimon, its the one you prefer having in your stack like BT2 Keramon, without setup you'll basically evolve into Diaboro for 2, and it snowballs in the same way as the Keramon.
The BT5 is the one you want to see as fast as possible, because it plays Arata for free, and give Rush to everything with the same name, so your Diaboromon tokens become an immediate threat, and even if you see them late in the game, spawning tokens with rush can be extremelly scary.
EX6 Kurisarimon is the answer the deck have for Floodgates, Ukkomon, and its extremelly cheap if you delete something (a token), the Inherit is good too.
The Level 5 are extremelly basic, just De-Digivolve your opponents digimon like crazy with them, and remember sometimes paying 7 cost to play the EX6 one is the best play you can make.
Level 6 is where the fun finally starts to us, EX6 Diaboromon is your best Digimon and its just fantastic, spawning a token when digivolving, spawning a token when your opponent plays a digimon and even spawning a token at the start of your turn, is soooo good, and it even gives jamming AND blocker to every other Diaboro you have, including the ACE.
Diaboromon ACE is just a really good card, spawning a token when digivolving and when attacking, AND an all turns that deletes a Digimon when another Digimon is played, just a fantastic card, and sometimes you have so much memory that the overflow doesn't even hurt you.
And the final Digimon is the Armageddemon, play cost 16? No I just see a play cost 3 Digimon that deletes your opponents board, and have so many good effects, and because it says cards, you can even recycle your Digi-Eggs or Aratas that are in the trash, it was such an massive upgrade for the old Armageddemon.
Now let's talk about Beast Cyclone, it's a tech choice but having an army of Jamming Sec +1 Digimon is so scary, because when you don't find the Rush Kurisarimon it's hard to kill your opponent, but with Beast Cyclone it becomes so much easier, because basically your whole board will have Jamming and Sec +1, so just do the maths and send your opponent to the Shadow Realm.
I really like Scramble in this deck because of the 2 Keramon searcher we have, and the Kurisarimon that gives rush, AND because of Armageddemon, we can recycle it anytime we want, and even the effect main effect is good, you just evolve into Infermon ou Diaboromon for 2 memory, really good card.
Black Training I don't need to explain, it searches for everything in the deck and make the evolution cheaper, just fantastic.
And finally Arata, Arata is the card that you live and die, he makes every Diaboromon so much better, that 1 extra token that he gives you makes the difference, and just by having 1 Digimon with the Unidentified Trait in the trash you gain 1 extra memory every turn.
And for the Side Deck, it really isn't a Side Deck, it's just other options you can try that I find interesting, let's talk about them quickly.
The "Warp Infermon" is a good option for obvious reasons, sometimes you don't have your level 4, so its the only play, and it makes the Diaboromon ACE even easier to make in the early game.
Catastrophe Cannon is searchable with EX6 Keramon, De-Digivolve 2 is a strong effect (even though you deck don't really needs it), and I mean, its spawns a token and it's a card that Armageddemon can recycle too.
Promo Diaboromon is a fun card that can potentially check your opponent entire security with just one attack.
Pride Memory Boost even though is pricey and can only play the Level 3, it trashes the other cards, which is good for Armageddemon and for Arata too, so it's an option you can try.
Mamemon even it's not searchable, it's kinda cheap to play, it searches and plays your Arata, and rearrange your deck, and works extremely well with Diaboromon ACE, remember, Counter Time is AFTER When Attacking, and BEFORE Blocker Phase.
BT17 Tsumemon can be good but I just don't like it that much.
BT16 Ukkomon is fantastic everyone knows it, it's another way to search for Arata, so it can be helpful.
Izzy Izumi he's just a "3 Cost Memory Setter" and rearrange your deck order.
Tai Kamiya is another Memory Setter but he have and useful effect, so you can try he.
BT17 Keramon seems good, but I don't feel like using it, if you want to try go for it!
And another card I want to mention is Quartzmon, the Level 3s can search it, so it's and option, but I don't like Quartz in this that, I used it in older decklist, and I never evolved into it.
And about Doomsday Clock, that card sucks.
Now Bandai give us a new Arata, that is a Memory Setter and the deck will be fire!
