Complex sentence: When Ozomu arrived at the gates, he realized that enormous powers lay within the gates and that even Jedah would destroy himself if he absorbed all this power at once and saw this as his chance to take over the throne.
Split into simpler sentences: When Ozomu arrived at the gates, he realized that enormous powers lay within the gates. He realized that even Jedah would destroy himself if he absorbed all this power at once and sees this as his chance to take over the throne.