Using “nor” in a list without “neither”

Question

This is the classic usage of neither/nor:

I would neither hide nor run away.

But is the following construction grammatical? (More than two choices, no neither)

I wasn't going to play dead.
I wasn't going to hide.
Nor was I going to run away.

Answer 1

Although the classic rule is to use neither and nor together, Grammar Girl writes:

“Nor” doesn’t necessarily have to appear in a sentence with the word “neither.” “Nor” can start a sentence. For example, if you’ve just mentioned that you don’t usually wake up at 6 a.m. and you want to continue being negative, you can start another sentence with “nor”: “Nor do I like to wake up at 5 a.m.”

Another option is to combine the two negative ideas into one sentence and then start the second part with “nor”: “I don’t usually wake up at 6 a.m., nor do I like to wake up at 5 a.m.”

In your case, you have three options. From the above, it is correct that you don't need to use neither. However, in the same article Grammar Girl writes:

You may also use “nor” if you’re talking about more than two items, but you must repeat “nor” after each element (2). So if you want to add ketchup to your list of dislikes, you have to say, “I like neither hot dogs nor mustard nor ketchup.” It would be incorrect to use an “or” anywhere in that sentence—or to leave out either case of “nor.”

So taking your list as even a single sentence, I think you need to repeat nor. So you could write (note grammar change in the second sentence):

I wasn't going to play dead.

Nor was I going to hide.

Nor was I going to run away.

Answer 2

Nor can be used without neither, as in the following sentences:

The struggle did not end, nor was it any less diminished.
Nor God nor demon can undo the done.

Answer 3

Where the preceding clause or the preceding sentence is already in the negative, as opposed to a positive one following neither, it is logical to equate it with a neither+[positive]:

neither+[positive] ... nor

Neither was I going to hide, nor (was I going to) run away.

[negative] ... nor

I wasn't going to hide. Nor (was I going to) run away.

I don't know of a proper grammatical explanation of this, though.