|Toaru Majutsu no Index Volume 20|
|Date of Release||March 10, 2010|
|ISBN Numbers|| ISBN 4048683937|
|Number of Pages||371 pages|
|Cover Character/s||Kamijou Touma and Lessar|
|Previous Volume||Volume 19|
|Next Volume||Volume 21|
Russia declared the beginning of the Third World War.
The conflict between Academy City and Russia will expand to the level where it will involve all other nations. The ones behind the scenes manipulating it all are the last member of "God’s Right Seat" and the bearer of the "Holy Right", Fiamma, and the man who watches and plans in secrecy, unknown to the rest of the world, Aleister Crowley.
In the fires of the World War, there is a group of people that runs to and fro.
A high school student of Academy City, Kamijou Touma, aiming to free an unconscious Index from the grasp of Fiamma after the incident of fighting over an artifact in England.
The strongest esper, Accelerator, aiming to save Last Order, who’s in a critical condition after the mysterious appearance of the entity "Aiwass".
Originally a lackey for the group ITEM, Hamazura Shiage, aiming to save Takitsubo Rikou who is physically weakened after she overdosed herself on the "powder" that boosted her abilities.
The three of them holding three different thoughts, three different paths that should never meet, converge in Russia. And what awaits them there is…
- Prologue: The Sky is Filled with the Scent of Gunpowder — Shooting_Game.
- Chapter 1: Good and Evil, Their Respective Entrance into the Country — World_War_III.
- Chapter 2: The Start of Attack and Counterattack — Angel_Stalker.
- Chapter 3: The Stand-Off Against the Wall of Doubt — Great_Complex.
- Chapter 4: Now is the Time to Strike Back — Heroes_Congregate.
- Epilogue: Battle Report