"No Game No Life" volume 3 by Kamiya Yuu. Readers learn in this volume that Sora and Shiro are really invincible due to their confidence in each other, like a single mind split across two bodies. Consistent with the earlier novels, this theme of confidence is demonstrated in many curious games.
First game is reversi (othello), but played such that Shiro must resume the game that Sora started by tracing back every single step to the beginning of when the game started based on Sora's personality. This was actually a convoluted scheme to exchange memory and gain allies for the next game, but it was arranged in a very interesting way. It's not very often that memory and personal existence are something to be wagered.
Second game is a shooting game, played using a very calculated scheme by Shiro. Despite the lack of communication between Shiro and Sora, the two still managed to coordinate a victory based on their confidence in how the other person would respond. The play-by-play narration of how each bounce shot was calculated was very fun to read, even more so when readers find out that it was merely a diversion for the next long distance sniper shot. And those shots were really just diversions for the well calculated final ambush that resulted in victory, but even that victory is merely just one step for Sora's greater political plan. It's layers upon layers of meta-games.
Volume 3 covers the last 4 episodes of the anime series, and most of the key dialogues have made it to the anime episodes. There is a sense of milestone with the end of this volume, since the series started with a video game and volume 3 ended with a video game. The series is still going though, maybe it really will end with world domination.
Previous (2014-09-10): "No Game No Life" volume 2 by Kamiya Yuu
Next (2014-09-25): Circuit scribe