I am getting a bit of a head start on this lesson. This lesson will be on side decking and not be complete, as I will cover individual cards later.
The side deck is 15 cards devoted for messing up the opponent, which ultimately helps the player using them in achieving victory. These cards are not universal to be good against every deck thus is not kept inside of the main deck. The side deck is vital for matches and tournaments, so vital in fact that our current test rubric has exactly one-fifth of all the accumulated points into it.
The side deck is used for matches (best 2 out of 3), not singles. The way it works is before the second and third duel (presuming there is one) in a match each player has a chance to swap out cards between their main deck and side deck. The main deck size must remain the same.
Strategies with making a side deck is making cards specifically for meta and decks you expect to see some of the time at a tournament or online match. It is recommended to stray away from cards that does not rely on what the opponent uses at all (as that is what would be deserving of the main deck) and cards that will hinder you.
Common side deck cards:
*Note: While not all these cards work well against one of the four top decks, these cards are often good in local tournaments. In these tournaments people often don't spend six-hundred dollars on a dragon ruler deck.*
Breakthrough Skill/Effect Veiler:
Both cards designed to negate the opponent's monster effects. Always nice for stopping a big eye or mecha phantom beast. A choice usually has to be made on which card to use. Breakthrough skill's effect works until the end of the turn, and ultimately can be used up to two times. Effect veiler activates from the hand, which is always nice, and is a tuner as well. Veiler however only lasts until the end phase, whereas breakthrough skill lasts until the end of the turn. Thus trigger effects in the end phase can not be negated by effect veiler, whereas breakthrough skill will. Unless the deck has a lot of synchro monsters that veiler can help push out, breakthrough skill is generally the better of the two.
Skill Drain:
Skill drain has always been a bit odd. Not only does it negate effects on the field, but it also stops effects that are not trigger effects (continuous effects) if it was activated before the monster was summoned/flip summoned. Works well for many evilswarm, six samurai, etc decks.
Mind Drain:
Stops all effects from the hand. This stops effect veiler, honest, dragon rulers (even blaster!) and any other card effect from the hand that starts a chain before being discarded.
Soul Drain:
This stops effects from the graveyard and banished ones. Be forewarned that this will not stop most monster effects from the grave/banished area that special summons themselves due to being summoning conditions. Cards such as grapha can still use their effects.
Imperial Iron Wall:
Stops many chaos decks, fairy decks, etc. Imperial Iron Wall stops cards being banished from the deck, hand. or graveyard. This slows down elemental dragons, partially prophecy, and can slow down tidal mermails.
Gozen Match/Rivalry of Warlords:
Not allowing the attempt even of summon a monster of a different attribute/type as another monster currently controlled by that player. Easily slows down dragon rulers (gozen), tidal mermails (rivalry), and evilswarm (rivalry. In addition there is older decks like macro/dino rabbit, lightsworn, chaos dragons, etc.
Maxx "C":
Nobody usually stops for maxx "c" anymore, but it is still a great card to draw many cards when playing against certain decks. Generally you avoid this for decks that do not special summon at least once a turn because then it starts to sit in the hand far too easily.
Flying "C":
This card isn't good against many decks except ones that don't have any synchro use for a level 3, and no monsters to tribute summon with. This excludes it to not being helpful against a wider variety of decks, but certainly heavily slows some decks.
Macro Cosmos:
Great for decks relying on discarding cards to the graveyard and the graveyard itself.
Mystical Space Typhoon/Dust Tornado:
Typically MST is before dust tornado. This is for the decks vulnerable to traps, such as a deck that often times takes 2 or 3 cards for one strong monster that can just as easily be taken off the field with one trap card.
Forbidden Lance:
Helps a lot with those trap and spell heavy decks as always.
Eradicator virus/deck devastation virus:
More so for decks with big-eye and dark world. They can demolish many decks,
Prohibition:
Sometimes there is that one card in the extra deck or that one card that is searched for easily that needs to be stopped.
Consecrated Light:
Currently the best dark attribute counter in my eyes. Unlike Shadow-Imprisoning Mirror, this card can stop monsters like grapha from being summoned via their own effect (why this is was covered in general lesson 1).
Stygian Durge:
Stops many xyz decks until it is destroyed.
Fossil Dyna pachycephalo:
Not only does it have an insane name i always screw up, it is a great card to set against most meta decks.
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