MONONOKE
Mononoke is classical Japanese horror anime. Main character is Medicine Seller who kill Mononoke (it's sort of demon). But he must uncover their form: Truth (Katachi), Form (Makoto) and Regret (Kotowari) and when he find this he can slay the Mononoke. It have very special design you can see connection with old Japanese classical art. It was direct by Kenji Nakamura and it have 12 episode.
Then when you want to have some special experience look for Mononoke (don't confuse whit Mononoke Hime).