Quite. Would anyone really complain if Shocker or Blade moved into the uncommon slot so we could get more Mysterios?

Ahh. I see how you're reading it now. It could certainly be more clear.

As per the first line of the trait, the dirt copy costs 70 points. As such, he is treated at 70 points for all effects. The last sentence is referring to the 15 point duplicate Mysterios only, as the first sentence covers the first copy.