While the Phantom Stranger has so far steered clear of actual paranormal activity, we get much closer in Phantom Stranger #4 (December 1952). A man experimenting with a book of spells has apparently summoned hairy demons and then has disappeared. The Phantom Stranger investigates and discovers strange hairy creatures. He captures one and convinces it to release the imprisoned man.
“Your formula, with those strange substances set afire, must have established a point of contact between dimensions allowing alien things from another plan to slip into our own dimension!”
The Phantom Stranger’s techno-babble in Phantom Stranger #4 (Dec 1952).
Why not just call them demons and magic spells, dude? Remember, any sufficiently advanced form of magic is indistinguishable from science-fiction techno-babble. Hat-tip, Arthur C. Clarke.