Hmmmmmmmmmm I wonder why

There are so many strong elder and those 9tiers and all those field looks so terrifyingly awesome but.... Why dont they used em when they were fighting with demons? And why only they show their awesomeness just within the competition? They can absolutely use those magnifying powers to crush demons easily tho ? They can reduce many deaths and consequential even without Hao Chen's help by the way they showing off their strength and power in the competition. Btw I love Hao Chen both his short hair(recent blond hair) he looks very handsome and his original purple black hair (he looks so cute) ε=ε=(ノ≧∇≦)ノ