Change to the Arena (PoL)

Make that the hero can also choose Knowledge in the Arena, instead of just Attack, Defense or Spell Power.

***** Edited 2017/08/25.

When a hero visits an Arena, all the Arenas on the map are considered visited by this hero.
It would be better so that each Arena to be considered independent, so the hero can choose different bonus for each of them.

Knowledge should remains tu some quiet/peaceful place I think... I kind of understand why it's "active attributes" only, in the Arena.

@GodRage

If you don't have enough spell points to cast your spells, then your Spell Power is useless.

That's not a reason!
In the Arena, you train "physical application" stuff... so why not Magic power. But Knowledge??? Sorry but for me it's a non-sense.

@GodRage

You should never underestimate the power of Knowledge.

Also, the player can simply ignore the Knowledge button and this leaves the gameplay unchanged. And the graphic is already present in the game files.