The Titan-Kaiju War is an event that taken place within the Triassic Period.

When the Precursors seek a new world to colonized within the Triassic Period but unable due to Earth being currently uninhabitable to them. When they discovered about the Hollow Earth and think it's the key for their survival, they unleashed beasts called Kaijus to find this Hollow Earth and take the power within it. However when the Kaijus set their foot on Earth, Dagon and many other of the Titans detected their presence and knowing these creatures are invaders, not part of the natural order. Both "protectors" and "destroyers" Titans temporarily work together to defeat the Kaijus and hope push them back were they came from. The Titan-Kaiju War was so powerful and dangerous that Pangaea slowly break apart and most lifeforms were killed, leaving the way for the evolution of the dinosaurs. After millions of years of fighting, the Precursors order their remaining Kaijus to retreat and the victory goes to the Titans but more than half of the Titan population were wipe out and radiation level were lower. This causes the Titans to hibernating for millions of years and heal from their large battle but a few will wake up within the next millennium thank to atomic bombing, pollution, etf.