Guard Selon:
The Giants Time ended long ago, and everything they built was destroyed long ago too... or so we thought. Maybe the death of Heavenly Island Ye Sagira woke the giants' monsters.
The private organization Embryo knew about this stone, and found the Giant Monster seed 'Sakum'... It seems like they had some reason for waking Sakum, though it's clear that it's failed.
"I see."