Shakugan no Shana Volume XXI (灼眼のシャナXXI) is the twenty-first volume of the Shakugan no Shana light novel series that is part of the main story and the twenty-fourth overall.
At EastEdge's place, Shana conveyed about CenterHill's last words and his resolve to fight this war against the Snake of the Festival to the remaining Four Gods of Mainland. After the conversation, all three decided to participated in this war. Also, a certain person is contacted at EastEdge's (highly possible to be Para of the Hyakki Yakō).
Meanwhile, many Denizens from all over the world started to come to Japan after Snake of the Festival's annunciation about his Xanadu (Utopia for every Denizen as he explained in Volume 20). Flame Haze at the main headquarters at Zurich clashed about the situation and resolution for this crisis but all to no avail.
Every Denizen under Bal Masque also arrived at Misaki City and Yūji took Kazumi with him to Seireiden to use her "image" of the City to reverse the Tuning Spell with "Anti Seal" from Volume 6  which will cause the already unstable dimension around Misaki City to break down, thus opening the Interval between worlds; where he would create the Xanadu.
Hecate was revealed to be the necessary sacrifice for the last process of God of Creation's Summoning as part of the system; every time the God of Creation sleeps, the priestess will appear and prepare for his return. After she is sacrificed for the Summoning, the God will create another "Hecate" again. She bid farewell to Sydonay and fulfilled her duty.
Dantalion activated the Saishuku no Shadan (宰祝の社壇, Shrine of Ruling Celebration), the fortress constructed inside Seireiden which would be the main instrument for creating Xanadu. This fortress also had the defense system; old-fashioned robots equipped with Kiken no Kentō, a system which creates a small vortex resembling the Pitfall of Eternity (the Spell that condemned Snake of the Festival into the Interval before) and could both deplete attacks from the enemy or the enemy him/herself.
Flame Haze - consisting of Shana, Wilhelmina, Chiara, Seere and the Three Gods of Mainland - attacked from four directions of Misaki City. Also, Denizens and Flame Haze were reaching the city, making it the Maelstrom of Warfare again. Khamsin managed to create the Rubble Giant using the ground where Saishuku no Shadan situated; it started to collapse but Sydonay used his Shintetsu Nyoi as the bracer for it, thus losing his weapon.
Shana reached Kazumi who was locked with Tartaros, Bel Peol's chain. She pledged Shana to cut the chain and, smiling, understanding now what she could do, activated the Giralda and an amber wind appeared...
|Light Novel Volumes|
|Main Story||I • II • III • IV • V • VI • VII • VIII • IX • X • XI • XII • XIII • XIV • XV • XVI • XVII • XVIII • XIX • XX • XXI • XXII|
|Side Stories||0 • S • M • SII • SIII|