I've been playing a lot of Symphony of the Night on my PSP now that I beat The Dracula X Chronicles, and I'm very amazed at the amount of originality when it comes to the various enemies in the game. Not only do they look really cool, but many have interesting backstories and connections to mythology I have never even heard of untill I looked them up on the internet.
The only thing that dissapoints me is that even though they re-did the script and voice acting, and added Maria as an unlockable playable character, they still didn't give the enemies their original names from the Japanese version of the game. Some of the new names I can live with, like the Salem Witch and Skelerang, but anyone who's even slightly familar with H.P. Lovecraft can tell that the Cthulu and Devil had their names switched.
But other then that, I have to say SotN has the best monsters of any video games because they're the most creative and original.
