Possession is nine tenths of the gore

Credit where credit's due, as far as I'm concerned the ideas in Lars von Triers's Antichrist were already explored with gruesome brilliance (and added cephalopod) in Andrzej Zulawski's 1981 movie Possession starring Sam Neill and featuring a staggering performance by Isabelle Adjani. With the long-awaited release of the movie on DVD you can verify this for yourselves.