With Antiok slain and the scythe in our possession, the frost wyrm assaults upon your forces at Angrathar will halt. The wyrms that remain in the Dragonblight will be hunted and destroyed, their bones returning to the earth.
My father was right about you, <name>. Everything that he said has come to pass - only one final duty remains unfulfilled. I will now lead the Kor'kron to the front line. The time to end this war is at hand. The Lich King's tyranny ends today!
Take my post now, <name>, and stand guard over our forces.
Alexstrasza the Life-Binder says: [Draconic] Ashj zila gul kirasath lok ante il lok buras danashj Gul gul
Korialstrasz nods.
Korialstrasz says: They will not.
Alexstrasza the Life-Binder whispers: Come to me, <name>.
In Draconic "Ashj zila gul kirasath lok ante il lok buras danashj Gul gul" means "They must not discover the fate of the young paladin" (Bolvar Fordragon). "Not yet." when run through the in-game translator.
This used to lead to the quest Darkness Stirs, but that quest and the remainder of the quest line were removed with Cataclysm. Reading through these quests offers answers for any questions players may have who come to the now-abrupt end to the chain.