Welcome to my newest installment of decks and techs! I have been meaning to make one of these for a while, today we will be talking about a very important theory in Yugioh, something called the Floater Theory, or the plus/minus theory. Now, before we can get into what a floater is, lets start with the Plus/Minus theory.
The Plus/Minus Theory is a theory that helps show weather a card will generate advantage for you. For most cases, this theory puts four portions of cards into the spotlight, the player's hands, fields, graveyards, decks. Now, if you gain card advantage(for example, adding a card from your deck to your hand) that is considered +1, in the same way, losing card advantage (sending a card from your hand to the graveyard) is considered a -1. Now let's look at an example.
Lets say you normal summon a monster from your hand. You sent a card from your hand to the field. Anytime you lose cards from your hand, that's a -1. However, adding cards to the field is +1. Now that means that normal summoning is a +0 in general(but not always). This is when floaters come into play.
A Floater is a card that replaces itself on the field. A prime example of this are the Gadget cards. When they are summoned, they get another gadget from your deck, so summoning a gadget would work like this
-Get Gadget from your deck(+1)
-Add card to the field(+1)
So as you can see, floaters(like the gadgets) are cards that can replace themselves. This can be a monster added to the field, hand, or (in some cases) the graveyard. This is why most top decks have some kind of floater (lonefire blossom, Shien's Smoke Signal, XX-Saber Darksoul, etc) understanding floaters is a very important thing in understanding how to win
Now lets look at a couple of other mechanics in the game.
-Synchro Summon: Now synchro monsters are some of the most powerful and broken cards in the game, but there is a reason for this. Lets take an example of sending Rose, Warrior of Revenge, and Summoner Monk, to the grave for the synchro summon of Stardust Dragon
-Send Rose to the grave(-1 from the field)
-Send Monk to the grave(-1 from the field)
-Summon Stardust Dragon(+1 to the field)
So as you can see, a synchro summon is always at least a -1, although it can be more (a problem with debris plant decks is they make huge minuses when synchro summoning, which is why they rely on swarming).
A special summon can be broken into several categories
A monster Special Summoned from the hand is a +0
A monster Special Summoned from the deck/graveyard/removed from play zone is a +1
A monster Special Summoned by the effect of a spell/trap from your hand is a -1
A monster Special Summoned by the effect of a spell/trap from your deck/graveyard/removed from play zone is a +0
A monster that is Special Summoned by the effect of a card in your hand is almost always a -1
Some more examples
Playing a spell or trap is a -1
Drawing a card is a +1 per drawn card
Fusion Summoning with Polymerization is a -2 (but can be more depending on the materials required)
Fusion Summoning via "Contact Fusion" or through Fusion Gate is a -1, however, playing fusion gate is a -1 in itself
Tribute summoning is a +0 or less depending on the number of tributes required.
Ritual Summoning can be expressed by y= (-n)+1 where n=the number of cards discarded/tributed for the summon of the ritual monster (this equation also works for synchroing and contact fusion)
So, as you can see, a lot of mechanics in the game give you minuses, but there are a few things to take into account that theory does not.
This theory does not take into account card effects that don't add/take cards from your hand/field/grave/deck
Ex: Say your opponent has 4 cards on the field, and you use the effect of Brionac, Dragon of the Ice Barrier and discard 4 cards.
Discard 4 cards (-4)
Bounce 4 of your opponent's cards(+4)
Add the bounced cards to the hand (-4)
So based on the theory, you just went -4. Now that may be true, but now Brionac has just set you up to do some big damage, so even though you went -4, you still got a very good effect, but the theory does not show that
-This theory does not add cards destroyed by battle
Put simply, if your monster attacks an opponent's monster and destroys it, it is not calculated as your opponent minusing or you plusing, it just kinda happens
Now, as you can see, the Plus/Minus theory is a good way to help understand Yugioh, but it is a flawed system. By this theory, there is no reason to run synchros, or even normal summon. So use this theory to see if a card is a +1,-2, or whatever, but it is not a good judge of if a card is good
Good Luck, and Happy Dueling