One of the hardest and yet the most important parts of playing on a competitive level is side decking. In my opinion, if you want to win on regional or higher level then you’re not going to win without a good side deck and a knowledge of other people’s side decks. Without the appropriate choices or knowledge you’ll loose to initially bad match-ups and you may loose to an opponent who can side well against your deck in specific.
First things first, the most important thing to know when making a side deck is to know what you’ll be siding for. You first want to think about siding for things you have a bad match-up with, but that’s not completely true. You may have a bad match-up against a deck like Chain Burn, but the chances of you playing them are so low that you shouldn’t expect to play against them or even side for it. On the other hand, in a format like today’s, it’s almost a given that you’ll play an Agent deck of some form, so that’s something your side deck should be prepared for as opposed to Chain Burn.
The second thing to look at is what of the pool of decks that you could possibly see are(which is actually fairly large in the current meta-game), and figure out which of them your deck will have a problem with. Once you’ve found those decks, then you look for cards that can help against the specified deck. That doesn’t mean only side for the decks that your bad against, but they should be the priority. Cards you can side can be anything from something as direct a counter as Puppet Plant against Six Samurai’s or as ambiguous as Thunder King Rai-oh who’s good against nearly everything it seems.
On that note, it’s also very important to make your side deck options very universal, but there are exceptions. You want to keep the choices in your side deck very helpful for more than one deck since 15 cards isn’t enough cards to side specific cards for nearly 20 possible decks. That’s why you want to side something like Thunder King, who can be sided for multiple decks like Plant Synchro, Agents or Six Samurai. Sometimes though, in the case of this format, one deck seems to have an overwhelming power over the rest and sometimes you just need to side something extremely specific like Leeching the Light that works incredibly well against Agents or a card in the past like Puppet Plant against Six Samurai. Some good ambiguous cards to side include D.D. Crow (for any deck reliant on the Graveyard), Smashing Ground/Penguin Soldier(good for killing problems your deck may not be able to easily deal with aka Kristya and the like) and Effect Veiler. (which should probably be in the main deck this format because it’s good against nearly everything)
Sometimes though, you’re running a deck that very vulnerable to specific siding options. An example would be Frog Monarchs, which are extremely vulnerable when people side in “graveyard hate”. (cards that mess with your graveyard’s cards) You should take this into account when siding. In this case you may side in cards that work specifically against sided cards like Different Dimension Burial for removal of Treeborn Frog or alternate Summoning Options like Cyber Dragon. It’s also important to play differently in game 2 and 3 since you know they’ve sided in. Know the cards they play against you and play around them. Know which cards you have that are “outs” (cards that supply an answer to a bad situation) and save them for the right situations. If you know that an opponent has likely sided in a card like Chain Disappearance when you’re running a frog deck, it’s better to be more wary about reviving your Treeborn Frog before a card like that is dealt with.
To choose the right kind of cards to side you need to know how other decks work. I’ve seen many cases where people go into game two having appropriate cards in the side deck, but not siding them in because they didn’t know the opponent’s deck well enough. Something like siding in Nobleman of Crossout against X-Sabers isn’t immediately obvious unless you know how the deck works and you know that they rely heavily on there own set monsters. To know what to side for really look at the things the deck relies on for success. As an example, when looking at a Plant Synchro styled deck you can tell they have a lot of monsters that have one time summoning effects (Debris Dragon, Junk Synchron, Tour Guide etc.) this makes them easy to shut down with Effect Veiler. Most of their key plays also rely on revival from the graveyard with either Debris, Junk Synchron or any of the plant monsters that revive themselves like Spore or Glow-up Bulb, which means D.D. Crow would work really well against them. Also, since the deck can do much without Special Summoning this makes Thunder King Rai-oh an appropriate side deck choice as well.
Lastly, there’s also one other style of siding, which is risky but can pay off, and that’s siding in another deck altogether. You can’t side in a completely different deck, but with 15 cards your play style can completely change. One of the most popular ways to do this is to side in stun. (it’s a really slow deck with lots of back row and really big beatsticks) Most big decks are really bad against stun in game 1 but once they side in game 2 stun isn’t as big a problem, but when siding in Stun it’s like making game 2 like game 1 where the opponent is at a disadvantage hopefully allowing you to win. You can also side in a different deck to counteract the weaknesses of your deck so they can’t be exploited game two, although this is a lot harder to do. This usually is the case for decks that are a one trick pony so going into game 2 you want to be playing something different, decks like Chain Burn or Final Countdown (weird stuff like that) can side in a more reliable deck like Agents or Junk Doppel if they where already running some of those cards in the main deck. A good example of this is if a Dragon Draw Exodia player where to side in Red Eyes Darkness Metal Dragon’s game 2 and some other offensive support.
So here’s a basic rundown; side for decks that are being played, side for decks your deck is bad against, side against sides that may give you a problem. Make sure you side cards that counteract the core mechanics of opposing decks and hopefully be able to side cards that work against multiple decks. And keep in mind you can always side in a different deck style altogether. As an example I’ll run down some popular side deck choices against a deck like Agents so you can hopefully better understand the side deck.
Against Agents there’s a couple weaknesses that are exploitable. First, they’ve got a lot of important monsters that rely on the graveyard, namely Kristya and Hyperion whom are usually keys to their victory so they’ll be important to stop game 2. Second, they search like the dickens with Earth and Duality building the deck’s consistency and if we can stop this they’re likely to fall on their faces. They also have some really powerful effects that play from the hand to the graveyard (Honest and Herald of Orange Light), which can heavily disrupt your plays. Taking these into account here’s some good sides:
- Dimensional Fissure: This shuts off all the graveyard build up of fairies that the deck’s Boss Monsters rely on and also disallows to use of cards like Honest and Orange Light since they must be sent to the graveyard to activate. This will make a lot of dead cards in the opponent’s hand and the opponent less likely to do any power plays against you. Unfortunately, this card can hurt most decks (even the one you’re playing) so it’s not always the best choice unless you are almost unaffected by it.
- Mind Crush: As I said, Agents search a lot from the deck which can gives you lots of information about their hand. With Mind Crush you can punish them for giving you that information by discarding their cards as well as seeing their whole hand.
- Thunder King Rai-oh: Similar to Mind Crush except it doesn’t even let the opponent search. It also can negate all the big inherent Special Summons like Hyperion, Kristya and even Gachi Gachi Gantetsu.
- Bottomless Trap Hole: There’s a lot of cards in this deck that hit by this card and most important is Venus. Using Venus to bring out Gantetsu is one the decks core plays and it’s completely turned off by Bottomless Trap Hole and it also removes the Venus from play preventing future Hyperion plays. It’s also very effective at killing Kristya on the spot.
- Smashing Ground/Leeching the Light: Archlord Kristya is really a jerk once it hits the field and a lot of decks don’t have any answers, outside of Dark Hole, in the main deck that can take it out once it hits the field. Both Smashing Ground and Leeching the Light can be answers to it once on the field. Leeching the Light is clearly a superior card against Agents since it pretty much devastates the deck even outside of Kristya plays. On the other hand it’s almost useless against every other deck making a lot of players opt for Smashing Ground instead since it is useful against practically every deck out there in more situations than the main reason it’s in the side in the first place.