Gaiden Volume - Practical War Game

is a Gaiden volume of the  of the  No Game No Life (Series)  Light Novel series, published on December 23, 2016. It was released in two different editions, the regular one and a special  limited edition, that was bundled with a Sora Nendoroid.

Plots
The Gaiden covers six short stories including different characters about their exploits in different periods

Abstract war game

As Sora plays chess with Feel Nirvalen to test the effect of her Magic after the two "joined" Elchea Federation, they begin to talk about Nina Cliffe and Shinku Nilvalen---the two magic casters who were given the title of Corolla, with abilities superior to their descendant.

Practical war game

The story never told about the game of Shinku Nilvalen, Nina Cliffe against Ronnie de Launier. How the former taste her first defeat in the device of latter, the exact relationship between two Corollas, the creation of "Protections", and the end of the war in their own sight...

Three times to repeat the game

As she plays a desperate game against Sora to prove the fact she isn't an idiot, and the Imanity 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.

Is on the card or peach flush

Chlammy Zell reminiscence her life from an incident that occurred a few months before her defeat at the hand of Kuhaku and their coronation, which pushed Feel Nirvalen 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.

Highcard all Raise Vol 1

During the Great War, Flügel committed many atrocities in the name of Artosh, their creator and the God of War. However, Raphael and Azriel noted the mightiest figure in the world rarely smiled ever since slaying Hartyrave himself, except being challenged by their youngest sister, Jibril. As the Valkyries continue their daily battle, Jibril decided to challenge a Dragonia by herself.

Highcard all Raise Vol 2

After suffering defeat six times in the hands of the White Dragon, Jibril gain the habit of writing a diary and learned elf language in order to defeat dragon. Meanwhile, Azriel decided to stop the extra unit by force if necessary. Looking at the acts, decisions, and accomplishments of his creations, Artosh slowly remembers the true meaning behind the extra unit...