It took six years to get a Night of the Demons sequel off the ground, which means that the primary antagonist doesn't hold up suuuper well to scrutiny as an immortal-undead possession-case. But Night of the Demons 2 is like... 99% as much fun as the first movie, which is a pretty good CV given the record of these sorts of sequels.

Final rating:★★★ - I liked it. Would personally recommend you give it a go.