The Borean Tundra, indeed, possesses a unique geography. Surrounded by the sea on three sides, its northern expanse gives way to the foothills of the Sholazar Basin, while Wintergrasp Lake lies to its northeast, nestled amongst the Sholazar Basin, Borean Tundra, Dragonblight, and Icecrown Glacier. Despite its perennial ice cover, Wintergrasp Lake remains the largest body of fresh water in Northrend.
Galen recalled the Sholazar Basin, sheltered by mountains, as a haven of life in the otherwise harsh continent. Its climate, markedly different from the surrounding lands, supported a diverse array of primitive wildlife, much like Kalimdor's Un'Goro Crater – both remnants of Titan biological research. To this day, Galen's scouts had yet to discover a viable land route into the basin, suggesting that traversing the mountains by air was the most expedient option.
Currently, Naxxanar stood as the Scourge's primary stronghold in the Borean Tundra. Its capture would signify the completion of the region's conquest. Originally a border city of the Azjol-Nerub spider kingdom, Naxxanar became a Scourge bastion after the Lich King's victory. Rumor held that a special envoy of the Lich King resided within its walls, a figure who commanded a significant portion of the Borean Tundra's undead forces. The city's inhabitants included not only Nerubians but also liches, human necromancers, and even a considerable vampire presence.
With the Lich King currently in a dormant state and the bulk of his elite forces guarding Icecrown Citadel, the Scourge had been forced into a series of strategic redeployments in the face of the Alliance's growing military might. The sudden appearance of the sky city of Dalaran had further heightened the alert status of northern Naxxanar. Even the skies above were now reinforced, with the third massive floating city of Naxxramas joining Tarren Mill and Naxxanar itself. The holy city of Naxxanar had become a formidable obstacle.
Intelligence gleaned from the Tuskarr allies revealed that after the Nerubians' transformation into undead, they had erected five necromantic towers within the city and its outskirts: Blood, Profane, Pain, Decay, and Lament. Three stood within the city walls, while two were positioned outside. Each sinister tower was guarded by a Nerubian lord or a powerful Scourge figure. Galen understood that these necromantic towers served as command and control hubs for the lower ranks of the undead. To truly break the Scourge's hold, these signal towers would need to be destroyed.
Galen's will dictated the Crusade's advance. The sky city of Dalaran ascended into the clouds above Valgarde and vanished from sight. On the ground, the Third and Fourth Crusader Legions garrisoned Valgarde and Fort Courage. The Templar Knights, led by Gavinrad the Dire; the Knights of the Silver Hand, under Baron Tyrosus; the newly formed Tyr's Guard Knights, commanded by Thaddius; and the First and Second Crusader Knight Orders – these five knight orders formed the spearhead of this offensive. Furthermore, the Borean Tundra's flat terrain was ideal for cavalry operations, and Galen had deployed all five knight orders simultaneously. His Origin Heart's troop production had reached a stage of mass output. He no longer favored ordinary infantry and riflemen; cavalry was his preferred unit type. Paladins, high-ranking knights, knight commanders, and royal guards – these elite units could charge on horseback, and dismounted… they could still charge! Beyond their martial prowess, the sheer spectacle of thousands of horses thundering across the ice filled him with exhilaration.
In addition to the five knight orders, the Tuskarr, Yak, and Mammoth people of the Borean Tundra, hearing of the Crusade's impending attack on the undead, spontaneously armed themselves and joined the Crusader army, eager to cooperate in the battle.
The Scourge could not have remained oblivious to such a significant movement by the Crusade. Within the colossal floating city of Naxxramas, the lich Kel'Thuzad, amplifying his vision through arcane magic, felt a cold dread grip him as he beheld the dense mass of knights on the ice below. The Alliance's war reserves were terrifyingly vast! Tens of thousands of high-ranking knights! He couldn't help but compare it to the Lich King's efforts – the countless races destroyed, the elite souls collected, barely amounting to three thousand Black Knights!
"Fortunately," Kel'Thuzad muttered, "we have three floating cities here. No matter how potent their cavalry, they cannot fight in the skies indefinitely!"
Yet, the very next moment, a tremor of unease ran through Kel'Thuzad. He looked upwards towards the clouds as a gargantuan city pierced the white expanse, dwarfing Naxxramas with a base at least four times its size and a sprawling cityscape. Soon, Kel'Thuzad's gaze locked onto the source of his apprehension: the Violet Citadel spire at the heart of Dalaran. There, a fiery red light was intensifying. The brilliance of flame magic illuminated the spire, and fiery runes began to flicker within the Eye of Rukhmar atop its hexagonal cone. These runes, radiating intense solar flame fluctuations, converged in mid-air with breathtaking grandeur.
Boom! A blazing ray of sunlight broke through the clouds, was channeled to the spire, and then reflected outwards, transforming into a scarlet beam of light that streaked across the sky, impacting the massive floating fortress with tremendous force. Kel'Thuzad felt Naxxramas shudder violently!
"Quick! Quick! Activate the shield!" Following the Great Lich's command, a vast surge of dark energy erupted from the floating city, instantly forming a hemispherical magical barrier around the entire fortress!
"It held…" Kel'Thuzad breathed a sigh of relief, albeit a premature one.
"Lord Kel'Thuzad! Naxxramas's energy reserves are plummeting rapidly! If no action is taken, the shield will fail within two minutes!" A frantic necromancer rushed in from within Naxxramas, urgently reporting the dire situation to Kel'Thuzad.
Kel'Thuzad's eyes narrowed. Naxxramas was not only his aerial flagship but also a war weapon of great importance to the Lich King, and its destruction was unthinkable. "Gothik! Immediately order Naxxramas to move!"
"Yes! Great Lich!"
However, the Flame of Rukhmar's energy could rotate 360 degrees around the Eye of Rukhmar, and Naxxramas's sluggish movement could not even keep pace with the scarlet beam's velocity. Seeing this, Kel'Thuzad made a desperate decision. "Immediately siphon energy from the necromantic towers in Naxxanar below! We need to get away as quickly as possible!"
"But, Great Lich, doing so…" Reaper Gothik's tone was hesitant.
"Silence! Do as I command immediately!"
"Yes!"
In the next instant, Naxxramas began to draw energy from the ground. The magic gems atop the five necromantic towers dimmed and faded, and Naxxramas's ascent accelerated explosively, narrowly escaping the beam of light's destructive path.
It was just that… with Naxxramas gone, the scarlet beam of light, its trajectory unimpeded, slammed into the floating city that had been concealed directly behind Naxxramas with devastating force!
Boom!