Tier 1: Highly Competitive Meta Decks. 10% or more of tops, as ranked by Pojo. This will roughly correspond to Pojo's Tier 1, with some overlap into Pojo's Tier 2.
Tier 2: Semi-Competitive Meta Decks. Less than 10% of tops, as ranked by Pojo. Corresponds to the rest of Pojo's Tier 2, Pojo's Tier 3, and Rogue.
Tier 3: Semi-Competitive non-Meta/Rogue decks. 1-2 tops. Specifically includes decks that top small events or get lower rankings at medium events. Can also include decks that can potentially top but have not yet in a given format.
Tier 4: Casually Competitive non-meta decks. Decks that can compete at the locals level, but cannot top an event.
Archetype Explanation
ABC is a sub-archetype part of the A-to-Z series of LIGHT Machine Union monsters and support. The relevant boss monster in ABC is ABC-Dragon Buster, a Contact Fusion monster. The other main monsters in the deck include A-Assault Core, B-Buster Drake, C-Crush Wyvern, and Union Hangar. Due to the relatively low monster count, there are normally other engines mixed in with the deck. Popular inclusions are True Draco, Brilliant Fusion, Symphonic Warriors, the Galaxy Soldier Package and the Destrudo/Dragon Ravine engine.
Tier Ranking
ABCs are currently sitting in Tier 3. This is due to a lot of the natural counters to the deck being main decked in preparation against SPYRALs. The deck is also easily sided against which can make competitive matchups quite difficult. Cards such as System Down and Ghost Reaper & Winter Cherries targeted at ABC are still relatively common occurrences. The most recent large event was YCS San Diego in which we saw an ABC decklist make it as far as Top 4 losing only to the Winner of the entire event in the semi-finals making 3rd place overall.
We are hesitant to rank ABCs higher than tier 3 because this was the only representation shown and speaks more to the player than the deck itself. That said, the deck is definitely a viable deck in today's format and we wouldn't be surprised to see it top another event.
Decklists
ABCockadoodledoo
Xinyu Jiang brought back a resurgence of ABC in placing top 4 with his ABC decklist. The overall lower amount of letter ratios was to allow for runing a whopping 12 handtraps in the main deck. The highlight tech of his build is Cockadoodledoo which is what many ABC players used before Destrudo the Lost Dragon's Frisson as a way to go into Ancient Fairy Dragon. Destrudo became the more appealing option due to its searchability through Dragon Ravine. There is further synergy here due to the fact that the Ancient Fairy Dragon that gets summoned will allow the searching of Union Hangar. Cockadoodledoo, on the other hand, requires that its controller has a field spell to start, making it less useful. The player made up for this by maxing out on Terraforming, Union Hangar, and Set Rotation. The Set Rotation is something to be noted because it was dropped in a lot of other decks after being Limited. However, it is extremely potent against many other matchups, notably SPYRAL and Trickstars.
Following this he played max copies of Ash Blossom & Joyous Spring, Ghost Reaper & Winter Cherries, and Ghost Ogre & Snow Rabbit. He played 2 copies of Droll & Lock Bird and was unsure if he would play a 3rd as he opted not to play it due to not being able to get it for the tournament. His only non-synergistic Extra Deck Reaper option was SPYRAL Double Helix. He plays a 41 card deck with 2 Pot of Desires, which is something that is interesting to note especially with the Letter ratios, but it seemed to serve him well during this tournament.
His Side Deck was simple but effective: Kaijus, Artifact Package, Evenly Matched, and Spell card floodgates. Due to playing Cockadoodledoo, he was able to have PSY-Framelord Omega in his Extra Deck. ABC is a deck that is able to be mixed with many other packages and engines, but this build is the hope for competitive representation in the ratios of handtraps and using both Destrudo and Cockadoodledoo as Field Spell enablers which facilitates the main play openers of the deck.
Galaxy Brilliant ABC
Rodney Hartwell Jr.'s 1st Place for the Charlotte North Carolina Regional is something that is still a great template anyone looking to play ABCs. Notably, he isn't playing any copies of Ash Blossom & Joyous Spring which helps with the overall cost of the deck. The Galaxy Soldier package has always been relatively popular in ABC decks. By sending a LIGHT monster to the GY, you can SS out Galaxy Soldier and it will search another one which can also be summoned. This makes for an instant rank 5 which can mean Cyber Dragon Nova into Cyber Dragon Infinity. Transmodify is another card used to change a piece into Galaxy Soldier. This has the dual purpose of triggering the sent ABC piece's GY effects and getting Galaxy Soldier on to the field.
The Brilliant Fusion Engine also sees good use in this deck. Brilliant Fusion has a lot to offer to ABC, giving GY setup, an extra monster on the board for Link summoning and an extra Normal Summon to ensure all of the pieces of ABC are on the field. The deck is already made up exclusively of LIGHT monsters, but there are the additions of Electromagnetic Turtle and Performage Trick Clown as tech options to be sent with Brilliant Fusion or discarded with ABC Dragon Buster.
While this build is definitely still strong, it is far weaker than it was before the advent of Link Summoning as Union Hangar and Transmodify can no longer lead to a board that consists of both Cyber Dragon Infinity and ABC Dragon Buster. One or the other has to be preferred unless you can manage to summon a Link monster first. Fortunately, the combination of the Gadget monsters, Brilliant Fusion, and Trick Clown give the deck additional fodder with which to summon out a Decode Talker.
Tech Choices
Destrudo the Lost Dragon's Frisson
The core part of the engine is Destrudo the Lost Dragon's Frisson. This card can be sent to GY by Dragon's Ravine, setting it up to be summoned to the field if you control any level 6 or lower monster. Destrudo is primarily used to summon Ancient Fairy Dragon which can, in turn, destroy Dragon Ravine and the opponent's Field Spell to search a Union Hangar. Ancient Fairy Dragon also has the added benefit of being able to out the Set Rotation lock, something that is increasingly common with the meta relevance of SPYRAL and something that can prove particularly deadly to ABC.
The Dragon Ravine engine can also optionally run Supreme King Dragon Darkwurm as an additional target for Dragon's Ravine. This card can summon itself from the GY if there are no monsters on your field, giving it a similar purpose to Photon Thrasher.
In addition to these monsters, the Dragon Ravine engine also offers easier use of Set Rotation. This is an increasingly popular card in the meta as SPYRAL become more prevalent and can serve as a very strong counter against them. Set Rotation also increases the consistency with which ABC can get to Union Hangar which is key to getting out ABC Dragon Buster as fast as possible.
Cockadoodledoo
Cockadoodledoo offers flexibility in that it can be utilized as a Level 4 or Level 3 tuner meaning that it can be effectively used for r4nk, Level 8 Synchro, or Level 7 Synchro. It depends on the opponent's board state in terms of whether or not it can be Level 4 but going first the Level 7 Synchro is preferred as it allows for a set up similar to what Destrudo is used for. The pros of having Destrudo is that it is searchable through Dragon Ravine which can be searched.
Gadget
The Gadgets utilized are Gold Gadget and Silver Gadget which can Special Summon a Letter Piece from hand allowing for a quick r4nk or Link option. They also recur each other upon destruction which helps in their recovery. With the restriction of a singular Extra Monster Zone, r4nk spamming is not as viable. This means there isn't quite as much of an emphasis on the Gadgets as there was before, but they are still useful for getting out Decode Talker.
Brilliant Engine / Predaplant Package
Focusing on summoning Gem-Knight Seraphinite through Brilliant Fusion, this maxes out on Brilliant Fusion as the additional Normal Summon granted helps to get more Pieces out on the field. In addition, because Brilliant Fusion mills a LIGHT monster this can effectively guarantee an ABC-Dragon Buster from the start. Having to run a Gem-Knight monster is the con as it is quite dead in hand leading to the terminology of referring to non-synergistic 1-ofs as "Garnets" of the deck.
The Predaplant Package is an extension of the Brilliant Engine and consists of 3 Predaplant Ophrys Scorpio and 1 Predaplant Darlingtonia Cobra. The main benefit it offers is to search out Brilliant Fusion more quickly while also providing Link fodder. While this Package is undoubtedly very powerful, the additional inconsistency that it offers, having to be run alongside Brilliant Fusion, is usually enough to turn most ABC builds away from it. The advent of new Link monsters that more easily utilize the Predaplants might see this catch on more, however.
Galaxy Package
Using Galaxy Soldier as a way to easily Special Summon out Cyber Dragon Nova (and thus Cyber Dragon Infinity) helps for negation protection/disruption as well as providing an outlet to discard pieces for ABC Dragon Buster. Transmodify is also used as a way to send Pieces to GY and SS out Galaxy Soldier. As discussed above, however, the Link rules have diminished this engine's usefulness due to it often causing a conflict of interests between ABC and Decode Talker.
Symphonic Warrior Engine
This engine consists of 2-3 copies of Symphonic Warrior Guitaars and 1-2 copies of Symphonic Warrior Miccs.
Both cards are Machine monsters (unfortunately they are WIND), but the extra NS provided by Miccs give the engine value in the deck. The engine does largely function, however, as a more budget version of the Brilliant Fusion engine due to it costing a discard to start instead of sending a card from the deck to the GY.
Matchups
SPYRAL
As the primary deck of the format to beat, it is extremely important for the ABC player to have hand traps to fend off the opponent with until they are able to play. While not as consistent as they were before the November list, the SPYRAL board can be a blowout if it is allowed to be built unchecked, making it a necessity of the overall format for handtraps to be mained.
The fragility of SPYRALs comes from their focus on Laddering into larger boards, but when this process is stopped they will often have subpar boards. The main remaining threat in this case is SPYRAL Sleeper. Luckily, Dragon Buster is capable of tagging out and the pieces recover advantage off of destruction effects. SPYRAL Resort preventing targeting is a large annoyance to Dragon Buster, however.
The overall matchup leans in the favor of SPYRALs but ABCs are capable of holding their own when going first or when disrupting with the right hand traps. Outside of hand traps, Skill Drain can be a very powerful floodgate versus SPYRAL when going first.
Pendulum Magicians
The matchup can be actually pretty difficult for Pendulum Magicians as ABC, especially the purer builds, are able to outgrind Magicians in advantage. The opponent's arsenal in their Side and Extra Deck really determines the rest of the match after game 1. Although the deck isn't wildly popular at the higher levels of play, it's greater presence at smaller regionals and locals will cause many Pendulum players run counters like Ghost Reaper or System Down to shut out ABC.
Trickstar
ABC players may find themselves infuriated going against this deck if they get locked out of their hand with Droll & Lock Bird and Trickstar Reincarnation. If the ABC player is able to rely on the True Draco variant or make Dragon Buster without the help of Terraforming and Union Hangar then they should find themselves in a good position however.
Something interesting to counter Trickstar with are the same cards that many ABC decks already run to counter System Down: Union Scramble and Pot of Acquisitiveness. Both of these cards can help the ABC player recover advantage lost by Trickstar Reincarnation and can decisively swing a game back in the ABC player's favor. Set Rotation is also particularly powerful against Trickstar as many Trickstar players don't have an easy method to out the lock.
Paleozoic
Paleozoics are capable of outgrinding ABC's as the form of disruption from Dragon Buster is costly by requiring a card in hand. This makes you burn through resources much faster which is something that Paleo decks won't mind at all. Many of the cards run such as Paleozoic Olenoides and Paleozoic Canadia can also heavily disrupt plays by preventing Link summoning or stopping Union Hangar from successfully getting a search. The main cards to use in the matchup are Spell/Trap destruction cards such as Cosmic Cyclone and Twin Twisters to try and prevent the opponent from amassing too many Traps.
True Draco
ABCs have a pretty fair matchup against True Draco. Due to Dragon Buster's effect banishing as opposed to destroying, True Draco can easily lose the trades in advantage they normally gain from the GY effects of their Spells and Traps. ABC Dragon Buster can also run over Master Peace if there isn't a Diagram present and its ability to dodge being destroyed on the opponent's turn makes it a tricky card to handle.
The main cards to be used against the matchup include Spell/Trap removal and hand traps such as Ash Blossom & Joyous Spring, Ghost Ogre & Snow Rabbit, and Droll & Lock Bird.
