I used to read a lot of spooky stories as a kid; you name it, Lovecraft, Poe, Matheson, King... Lots of frightening stuff. However, these two largely unknown CYOA-style books were, hands down, the ones that scared me the most. To tell the truth, they're fairly average in retrospective and in no way comparable to the standards set by Edward Packard, but the writing was surprisingly moody and the inside drawings terrifying as hell.
In one particular dream sequence in Space Age Terrors!, you're kidnapped by an evil, distorted version of Goofy who locks you inside a rocket and launches you into space. Yeah, it sounds rather silly when I put it like that, but it was downright chilling in the book.
Such great memories! So which books scared you the most in your childhood?