What are all the magic words?

Hint 1 of 16:

The sixteen are:

Hint 2 of 16:

XYZZY (cobble crawl)

Hint 3 of 16:

PLUGH (Y2)

Hint 4 of 16:

FEE (Giant room)

Hint 5 of 16:

FIE (Giant room)

Hint 6 of 16:

FOE (Giant room)

Hint 7 of 16:

FOO (Giant room)

Hint 8 of 16:

MELENKURION (tool room)