Which heros are the best for arena cause I need some help so I can get the troop chips?

It depends which type of heroes you have

Keeping that in mind you can set a line up

I prefer fox (Healer) , ulrick (Armor reduction) ,zypher(defence), Mars (mana burn + damage)

One more damage dealer as you prefer

But you need to have at least one Healer and one mana burn helps a lot