Miku nodded. It was the right kind of question to ask. "Nigal intend to catch Arceus so he can have an infinite supply of Dialga, Palkia and Giratina's as well as possible taking control of the lake trio to control the people as its said that Mespirt, Azulf and Uxie gave humans emotion, Knowledge and Willpower" Miku told them. 
"That's at least what he tells the other pouchers, his actual plan is to travel back in time to change the events of the past, thoughout his long life, he was witness to many defining moments in history. He seeks to make himself the centre of every event to ensure the world goes on the path he wants" Akari added.