Deck Recipes are an aspect in many Yu-Gi-Oh! video games. They allow the player to use cards from their own trunk to load a character's Deck list, into one of their own Deck slots.
The player can obtain one Deck Recipe from each character that can duel against the player in regular duels, which corresponds to one Deck they use over the course of the game. The player must have that character registered as an acquintance before they will begin to offer their Deck Recipe, and they will randomly offer it after finishing a duel against them.
Deck Recipes from opponents who only face in the player in Shadow Games are unobtainable, with three exceptions - the Deck Recipes of Noah Kaiba, Gozaburo Kaiba and Yami Marik are obtained by finishing the Duel Courses in the Duel Base after the end of the game.
The mechanics from Nightmare Troubadour are carried over to Spirit Caller, but the player cannot obtain Deck Recipes from Shadow Game opponents in any way.
World Championship series
The player automatically obtains the Deck Recipe of any Structure Deck they purchase. In Over the Nexus, players also obtain the Deck Recipes associated to Rental Deck Duels used in duels against Noko by winning duels with those Decks.
Tag Force series
The player can duel against any of the Deck Recipes in their possession by setting it as Mimicry's Deck in Free Duel Mode. Recipes could also be downloaded, and they would be stored in a special, third tab present in the Recipe Viewer.
The availability and applications of Deck Recipes varied over the course of the series.
Tag Force 1
Most characters have only 1 Deck, and if the player has at least 10 victories registered against them, defeating them in a Single Duel in Part 1 will earn the player their Deck Recipe. Unlocking all the recipes from any opponent with multiple Deck Recipes needs the player to finish Part 3 with that character as the player's partner, with the exceptions of Blair, Amnael and Colin.
Tag Force 2
Each character now has at least 3 Deck Recipes, and they are obtained by finishing that character's storyline.
From this game onwards, Deck Recipes also denote which cards are set as Destiny Draws for that particular Recipe.
Tag Force 3
Finishing any story of a character with 2 or more storylines unlocks all of the Deck Recipes associated to that character due to a programming oversight.
Due to another mistake, when editing the Partner Deck of any such character after finishing one of their storylines, the player can reload their first recipe even when partnered with an alternate version of that character. This overrides all cards in their current Deck, including any possible favorite cards that would be otherwise impossible to remove.
Tag Force 4
The oversights in Tag Force 3 were addressed, and the player will now only obtain the recipes associated to the version of the character whose story was cleared. The player must see the character in another light and finish their other storylines to obtain the rest of their recipes, and the cards designated as favorites cannot be overridden.
Tag Force 5 and 6
Certain opponents in specific story events use Decks whose Recipes are not obtainable through legitimate gameplay.
Tag Force Special
Obtaining the Deck Recipes of any character that is not one of the 5 possible partners is done by defeating that character at least once and finishing all the storylines associated to that character's Duel World.