How to play against ABC
ABC-Dragon Buster is the most vulnerable during its controller's turn. They can't tag out, or dismantle, your choice of words. This is the reason you see cards such as Compulsory Evacuation Device being placed in side decks recently. The trap is most effectively used when targeted at Dragon Buster during your opponent's turn.
Being unable to escape the resolution effect of Device, you will go at most 2-for-1 if they decide to chain Buster's effect to remove a card on your field. You will have a very good exchange that is worth your card economics/advantage should they take the initiative to target your face down card, and it turns out to be Device. Just chain it, and you got yourself a one-for-one card exchange.
De-Fusion was seen during Dark Law's reign. Yes, it can be used on Dragon Buster. But why would you?
- Being able to tag out on your turn, they will do so to escape the effects of De-Fusion. They will incur a loss should they just accept their fate. So why not? Hence, it is not recommended for you to do that, and de-fuse Dragon Buster on YOUR turn.
- De-Fusion's main purpose back then was to act as a first-turn Compulsory Evacuation Device - being able to de-fuse and rid Dark Law. Unlike how you should counter Dark Law, a threat you should get rid of ASAP, Dragon Buster should be removed during their controllers' turn.
- Since you would rather remove that machine boss on their turn, you CAN indeed still run De-fusion. But won't it hence be more worthwhile to turn to a versatile option such as Compulsory, which ultimately serves the same purpose - Send their boss monster back to deck?
- Compulsory can even be used on other threats (E.g Cyber Nova Dragon)
- Until the meta sees more Fusion monsters, and the situation arises that you need more than three copies of Compulsory, De-Fusion should just be benched. Against ABC, this quick-play would probably only serve as a bait for them to start using their "discard-and-remove" effect and/or their "Transform and roll-out".
Compulsory, use it on their end phase. That way they can't perform the plays needed to help them recover from the loss of resources, (e.g. Set a monster to defend themselves, set a trap to defend themselves.) Should their field be empty, go for damage next turn. But even if you don't, without more searching/resources-recovering, they can't make Dragon Buster next turn.
Yuki Usagi / Ghost Ogre is effective against ABC. Use it to chain to their Cyber Infinity effect to destroy that troublesome beast. You will probably have to sacrifice a card to bait its effect though. Another usage of Yuki is when you destroy their field spell, Union Hanger, the one card responsible for assembling the needed ABC parts from the deck. Use it on their first turn and they will have a tough time recovering from it. Union Hanger can, after all, gather up to two alphabets from the deck onto the field. Stop Hanger and you would have slowed them down.
Starting with a Gadget summon probably means they do not have a field spell or access to it via Terraforming. You can 'Yuki Usagi' their gadget to prevent them from summoning Tsukiyomi. Being unable to discard their hand, they will either suffer from being unable to replenish their resources or stuck with a single ABC part on the field.
Should you have your own ABC-Dragon Buster, or cards such as Phoenix Wing Wind Blast, use it to target their first normal summon, not their field spell. Cyber Dragon Infinity should also be used to negate the trigger effect, and not the activation, of Union Hanger.
I repeat: First normal summon. ABC values their normal summon. Minus that and the only way they can gather their parts is via Galaxy Soldier. And by doing so, they can't abuse the alphabet's effects to upon entering the grave.
Mirror of the Ice Barrier can be used by ABC players as well, which is a reason why you should do your D.D. Crow and Cycle Reader plays early in the game, or suffer from a mirrored karma.
Nevertheless, Dragon Buster can't escape System Down alone.
Many ABC players would side in Mirror as a anti-side. Or for mirror-matches. So just watch out for that.
Solemn Strike, still relevant as ever, is a counter trap. This means that game mechanics can't allow players to negate it with monster effects, and monster effects can't chain to it - making it an effective method to get rid of Dragon Buster even with Infinity is on the field.
ConclusionLearn to sense their weakness, and see any openings in their plays. Should your opponent decide to overextend, try to strip them of their resources, bait, then punish them with a turning of tables.
Gather experience; be patient.
Should you have any more questions as to how or why, same old procedure - private message me on Facebook or Twitter (Left of the blog's main page). Dueling Cancer is also in the midst of setting up a DISCORD account.