Could someone explain to me why we have a side deck, how to use a side deck, and what are the advantages of having one? I've had the hardest time understanding it all

really? -_- Side decks are used to modify your deck in between duels in a match you can side for stuff you would use against other decks or cards that would go great with yours

Your side deck can contain up to 15 cards.

A match consists of 3 duels which I will call "Game 1", "Game 2" and "Game 3".
In the first game, you have to use your main deck. If you are in a tourney and you used your side deck in a match and then you are dueling your second opponent, you will first have do return your main deck and side deck to the way they originally were.

Using the side deck. Before Game 2, you can swap cards between your side deck dnf your main deck.
So long as You side in the excat amount of cards that you sided out.

Side deck allows you not only to surprise your opponent, but to gain advantage over his deck.

Some cards are doing great against specific decks, but bad against others.
You don't usually want such card in your Main Deck. I don't have a reason to use Concerete Light against LightSworn. But if I find myself Dueling Blackwings and have it in my Side Deck, I will "Side it in" for sure.

Between Game 2 and Game 3, siding is allowed as well.

Quote :

This is to say that if if you add cards from your Side Deck to the Main Deck, you odn't Necessarily have to "side out" a card from your Main Deck in return.

Incorrect

Quote :

Side-Deck
This is a separate Deck of cards you can use to change your Deck during
a Match. After each Duel in a Match, you can swap any card from your
Side Deck with a card from your Deck and/or Extra Deck to customize
your strategy against your opponent. The number of cards in your Side
Decks must not exceed 15. The number of cards in your Side Deck before
and after you swap any cards must be exactly the same.

Rulebook V7 page 2

haha e^ipi+2=1
Well, side deck is PRO even if i hate using it

e^ipi+2=1 wrote:

Quote :

This is to say that if if you add cards from your Side Deck to the Main Deck, you odn't Necessarily have to "side out" a card from your Main Deck in return.

Incorrect

Quote :

Side-Deck
This is a separate Deck of cards you can use to change your Deck during
a Match. After each Duel in a Match, you can swap any card from your
Side Deck with a card from your Deck and/or Extra Deck to customize
your strategy against your opponent. The number of cards in your Side
Decks must not exceed 15. The number of cards in your Side Deck before
and after you swap any cards must be exactly the same.

Rulebook V7 page 2

Fixed. Thanks for the info. O:

You can use a side Deck to side in important cards during a match. For example you fight a deck like Backwings and you cant beat it with your current deck. Then you can side in cards which can beat them.

Another use of the Side Deck is to switch the whole deck. For example if you want to switch from Meta Deck to Anti Meta if needed. (e.g. Monarch -> Macro Monarch) If you do this make sure that 15 cards switch the deck.