Gaiden Volume - Practical War Game

is a gaiden volume of the  of the  No Game No Life  series, published on December 23, 2016. It was released in two different editions, the special  limited edition that was bundled with a Sora Nendoroid, and the regular edition. On March 19, 2021, Yen Press announced their translation of Practical War Game with a release date set for September 21, 2021. On an unknown date however, the publication was pushed back to September 28, and on another unknown date it was further pushed back to October 5.

Story Details
|-|Synopsis= Before the creation of Disboard, a world where everything is decided by games, there raged a terrible war among the stars. But the Immanity weren’t the only ones fighting to end it-one Elf had her own dreams for the future: “Whoever’s left standing once all the stars are destroyed is the winner.” In other words: anything goes! Follow Think Nirvalen’s exploits during the Great War along with several out-of-this-world short stories originally included in the anime’s bonus features!

The gaiden volume covers six short stories including different characters about their exploits during different periods in time.
 * -|Summary=

Abstract War Game
As Sora plays chess with Fiel Nirvalen to test the effect of her Magic after the two "joined" the Commonwealth of Elkia, they begin to talk about Nina Clive and Think Nirvalenーthe two magic casters who were given the title of Gran Magus, with abilities superior to their descendant.

Practical War Game
The story never told about the game of Think Nirvalen, Nina Clive against Lóni Drauvnir. How the former taste her first defeat in the device of the latter, the exact relationship between two Gran Magus', the creation of "Spirit-Breaking Rites", and the end of the war in their own sight...

Threefold Repetition
As she plays a desperate game against Sora to prove she isn't an idiot, and the Immanity king had revealed his trick in the sleeve, a horrible incident occurs when Stephanie Dola finds herself paying a risky price to play on equal terms with Sora.

One Pair or Heart Straight Flush
Chlammy Zell reminisces her life from an incident that occurred a few months before her defeat at the hand of 『　』 and their coronation, which pushed Fiel to rebel against Elven Gard's corrupted hierarchy. After numerous events taken place, Chlammy has made use of Sora's trick she learned from his memories to take her revenge while the duo takes step toward their plans by tying up a loose end.

High Card All Raise Part 1
During the Great War, the Flügel committed many atrocities in the name of Artosh, their creator and the God of War. However, Rafil and Azril noted the mightiest figure in the world rarely smiled ever since slaying Hartyleif himself, except being challenged by their youngest sister, Jibril. As the Valkyries continue their daily battle, Jibril decided to challenge a Dragonia by herself.

High Card All Raise Part 2
After suffering 5 defeats in the hands of the White Dragon Lieschengerth, Jibril gain the habit of writing a diary and learned Elven language in order to defeat the dragon. Meanwhile, Azril decided to stop the extraordinary unit by force if necessary. Looking at the actions, decisions, and accomplishments of his creations, Artosh slowly remembers the true meaning behind the extraordinary number...

Chapters

 * Abstract War Game
 * Practical War Game
 * Threefold Repetition
 * One Pair or Heart Straight Flush
 * High Card All Raise Part 1
 * High Card All Raise Part 2

New Characters

 * Nina Clive
 * Unnamed Elven Admiral
 * Unnamed Elf in Black
 * Lóni Drauvnir
 * Five Unnamed Nirvalen Maids
 * Senator Noel (mentioned)
 * Senator Noel’s Butler (mentioned)
 * Lieschengerth

Illustrations
Gaiden Volume - Practical War Game