(Amazing-Man Comics 019, 1941)
Mighty Man was always a lot for crooks to deal with even when he was just a 12 foot tall guy with super strength but after he gained complete control over his physical form he really gave them a run for their money. I assume that's why he was assigned an actual, factual magic-using witch as a recurring enemy. At least, at first.
In her first appearance, the Witch had a magic broom that allowed her to fly, changer her shape, pass through walls and paralyze others (plus more, presumably). She came into conflict with Mighty Man over a munitions company executive who had the formula for a mind control gas and was understandably reluctant to reveal it to a gang of crooks. The Witch made her getaway, swearing revenge.
The Witch returns in Amazing-Man Comics 020 without her broom (no reason is given). She is now equipped with a potion that allows her to changer her appearance, which she uses first in an attempt to kill Mighty Man by claiming to herself be the targeted for assassination. This of course does not work, so in issue 21 she captures Mighty Man and declares that she will keep him prisoner until she discovers the secret of his powers.
This is where things get weird, dynamic-wise. The Witch's sedatives turn out not to work on Mighty Man, but he realizes that as her prisoner he is in a prime position to learn of and foil her various schemes. So for the next couple of issues (plus an issue of Stars and Stripes Comics), Mighty Man is theoretically paralyzed in a cell back at the Witch's hideout while actually sneaking around and shapechanging his way through the massed ranks of her criminal army.
The best thing to come out of all of this is this little kid super-hero identity that Mighty Man adopts and who I, like the Witch, like to call "Little Squirt", even though he technically never has a name. Mighty Man's writers eventually solved the problem of him being too powerful by having him assign himself the task of following Super-Ann around and helping her out without being seen by her, which is pretty fun but I kind of wish he'd leaned into this idea of fighting under different identities.
The Witch, meanwhile, eventually drowned in a flood during one of her many schemes. I'm sure she wished she still had that broom.
