Later chapters reveal that Pray learnt the initial basics that Pray Style is based off from a teacher, Karen Mayer, along with an entire dojo of classmates who also used techniques that resemble the Pray Style.
Her strikes commonly break DC Coats and defeat Beasts with her bare hands. Sometimes Pray is so brutal that even her AB Sword is destroyed. The most destructive aspect of this is the Pray Special Wave Technique.
In fact, this is not style nor skill. The true nature of Pray Style is a mental state that results in victory.
(Ep0 - Ch4): "The fundamentals of Pray Style are very simple. It channels pure power to blow away all attacks or defenses of the enemy".
(Ep0 - Ch15): "Many get wrong about Pray's power, but this isn't a Paranormal Power. This is her karma she acquired as a human, "MU". It's the strength she gained by training day by day endlessly, accumulating her "MU". She learnt human wisdom and experiences, upon which she devised her style, adding her karma. There might be an extent of her natural ability capacity, clever methods and creativity, she spent sufficient time to acquire these. The power she perfected with humanity's wisdom and training. What gave her the power she didn't have... was the earnest wish and all those days she spent training. That's probably the expression of her life in which she struggled so hard to protect 'someone'".