The Second Apocalypse is the successor conflict to the First Apocalypse, during which time the No-God was summoned by the Consult to bring about the annihilation of humankind and the sealing of the World against the Outside, thus saving a minority from damnation at the expense of the majority. The No-God was defeated at the Second Battle of Mengedda in 2155 by King Anaxophus V of Kyraneas, who used the Heron Spear, an Inchoroi spear of light, to penetrate the Sarcophagus and apparently kill the No-God. In some traditions, the Sarcophagus was completely incinerated and the ashes scattered across Eärwa, triggering the Indigo Plague. Mandate warnings to the contrary were ignored.
In reality, however, the Sarcophagus was only damaged, not destroyed. It was recovered by the Consult and returned to Golgotterath, where it was repaired to the best of their knowledge. The Consult then spent the next two thousand years attempt to reactivate the Sarcophagus. In 4132, at the conclusion of the Great Ordeal's disastrous campaign against Golgotterath, they succeeded. The Second Apocalypse has begun and the No-God walks the earth once more.
According to the Mandate tradition, Anasûrimbor Celmomas II, the High King of Kûniüri during the Apocalypse, prophesied that the No-God will in fact return but an Anasûrimbor would return to stop him. The prevention of the Second Apocalypse was the Mandate’s ultimate goal, in which they failed. It was Anasûrimbor Kellhus's campaign which in fact led to the Second Apocalypse, as the Consult wanted to trap Kellhus himself within the Sarcophagus. This failed and Kellhus was slain. His son Anasûrimbor Kelmomas was instead placed within the Sarcophagus, triggering the resurrection of the No-God, which promptly destroyed the Great Ordeal. The resurrection of the No-God triggered the beginning of the Second Years of the Crib, preventing the birth of any further children.
The outcome of the Second Apocalypse remains to be seen, but the destruction of the Great Ordeal has denuded the Three Seas of almost all men of fighting age and health. Only the military and sorcerous potential of the nation of Zeüm remains unspent. The No-God has access to far vaster numbers of sranc than existed during the First Apocalypse and the support of Dûnyain sorcerer-advisors, as well as the allegiance of the Scylvendi. The odds would appear hopeless.