Epic Cards Battle

What is the advantage of this card? The description is: "This card's enhancing effect is doubled."

Huh? What's doubled? I don't see anything increasing while it is playing. I'm surprised at how often I see this card used while dueling. What am I missing here?

When enhancing this card the stat boosts will be doubled for your investment, namely damage and HP. At level 30 it makes it a fairly tanky card but I don't find myself using it much.