suggestions

With this current energy system, the targets are very rare to chose from.
Please increase the attack level range because this is already frustrating having no one to fight with

The higher your level the bigger your attack range...

New range -> (Level * 1.35)
Old range -> ((Level * 1.35) + 2)

When you are level 2, you should be able to fight level 5's. And when you are level 9, you should be able to fight level 15's. But...Not anymore.

New range -> (Level * 1.35)

Is this accurate?

Yes