It's not about the hero type.

It is about the hero skill!

You see the below hero is a Defense Type hero.

The reason why is because when you upgrade this champion the defense of this champion will scale up.

However, if you want this champions first move to hit really hard, You would have to put some Attack on him.

You can see this champions A1 Shield Bash deals damage based on his Attack.

Let me give you some more Examples to really drive home the message!

Example 1:

Lets say the above move Shield Bash said Damage based on: [DEF] 

You wouldn't need Attack on this champion,

You would want to add more Defense for them to hit harder.

Example 2:

Lets say the above move Shield Bash said Damage based on: [HP]

You wouldn't need Attack or Defense on this champion.

You would want to add more Health for them to hit harder.

Example 3:

Lets say the above move Shield Bash said Damage based on: [ATK][DEF] 

You wouldn't need Health on this champion.

You would want both Attack & Defense for them to hit harder.



Also, you should be aware if a hero has a Double Damage Base (Like Example 3) 

The first base amount has the higher multiplier.

The first base amount on Example 3 would be the [ATK].