Fiend (1980) 
Don Dohler's Fiend is a little step down in the effects department in comparison to his prior film The Alien Factor, which exhibited a veritable buffet of cheesy '80s visual treats and of which enhanced the enjoyment factor of the film considerably.
Fiend is more grounded in its effects, in as much as you get some glowing red aura cropping up here and there as well as some minor prosthetic make-up. The film instead is a more sinister, mysterious tale involving corpse re-animation by some kind of energy based entity which requires life force to survive. Now in its re-animated body, the entity takes up residence in a small town suburb teaching violin as its austere Orson Welles-esque host used to do whilst taking frequent breaks in order to drain the local town's people of their life essence by throttling them.
As a Dohler film, you pretty much know what you're going to get going into it, and as minimal budget '80s schlockfests go, you can certainly do a lot worse than this.