Ruling Special Metal Energy + Skarmory's Steel Wing?

[Monsterblood12]

I was wondering, if you attack with a pokemon such as Skarmory using the attack steel wing, and you happen to have a shield energy (or the old special metal energies, same thing) attached to skarmory, will the prevented damage stack? For example, the attack prevents 20 damage done to skarmory next turn. a shield energy prevents 10. will that then be preventing 30 damage, or even more, depending on how many shield energies you have attached? This is always the way I played, (I built a tank deck using this strategy) however, I am now questioning if it is legal or not, even in unlimited

P.S. - I just realized the old metal energy and the new shield energy are worded quite differently.

How does this situation I asked about apply with either energy?
Also, I feel like the old special energy is more important because that is one I have most of and use in my deck

 

[Mora]

RE: Special Metal Energy + attack that prevents set amount of damage...?

Yes they would stack. If you have two Special Metal attached and used Steel Wing, you would reduce a total of 40 damage. 20 from the attack plus 10 for each Special Metal.