IIRC, you have to do a series of quests for the Mad Scientist so he'll build the helmet for you. After that, it's in your inventory and you can equip it like any hat.

I just double-checked my hats, and there is definitely a powered battle helmet in there. I can't for the life of me remember what the scientist asked me to do, though. Did you need to do something for the blacksmith?

i have fished and fished in the Shadow of the Mountain. are you sure that is where i get it. cause yes my haunted castle is at 100%, and no quests. what does it look like, i am 99.9% i've checked all my hats and none of them have that name or a description that says it will help me. the black smith does not have a hat in any of the drop down's. STUMPED

When I said fished up in the Shadow of the Mountain, I mean fishing there at the request of a scientists Castle quest. If you are not doing that quest then you can fish till the cows come home and get nothing but gold and energy and junk.

p.s. I seem to remember something in the Castle that was Level dependent, you wouldn't get a quest, even if you completed the area to 100%, until you reached a certain Level. Perhaps this has been messed up by the Magic something-or-other that the Developers added to the game for lower level players a very very long time ago.