Ideally the roles are called the 'protagonist' the main character the 'good guy'. 'Antagonist' would be the inflictor.

I prefer the protagonist almost always. One of the most powerful aspects of horror is the clear dileniation between protagonists and antagonists. There are the good guys and there are the bad guys. There is an effort to try and take a post-modern approach that tries to make the good guys less good or operating in some grey area but this falls flat in ny opinion.

I do think a perspective switch that describes various scenes from the perspective of the antagonist can be good. Like scenes from The Bighead that describe his movement and adventures through the woods.