Board Thread:Questions and Answers/@comment-27327020-20160404174206/@comment-13682699-20170412031614

He was using intimidation tactics to make them give up.

His power is still virtually limitless based on his intent. Ever heard of "the whole is greater than the sum of its parts?" this quote describes this scenario quite well. While we cannot say his power is absolutely infinite (there is no such thing simply because infinity is a concept) his power is immeasurable to a degree that it cannot be quantified by any finite means, hence why his ATK/DEF stats are basically off the charts.

Also, he has already created a separate dimension/world with only 6 souls which is known as Flowey's World when you fight him.