Best soundrack ever.
Graphics: The best of all the side-scrolling Castlevanias. Many enemies are large, and each has its own destruction animation. The castle is massive; you will travel thru many environments with rich detail and tons of colors. Many of the weapons have unique looks and special effects. Bosses are extra big and nasty. Visual effects are exciting and sometimes startling.. not the least of which is when the castle turns upside down.
Sound: The soundtrack is a classic. The classical-style pieces evoke many different moods. Instrumentation ranges from violins and upright basses to harpsichords, to full thrash metal band. The sound effects are many and varied. Many creatures scream as they explode/melt/burn/vanish/etc. The characters' voices are wonderfully campy.
Playability: The closest comparison is Super Metroid because you will need to backtrack through areas to find or use a new ability to further explore the castle. This works well because you will slay more fiends, which will raise the protaganist's level. Hidden rooms abound, secret weapons and spells and familiars are everywhere. You can spend 20 hours exploring the castle and still not have covered the 200% (and beyond) of map.
Overall, this is an excellent game. If you have a PS or PS2, try this game out. If you were a fan of Super Metroid, do not finish reading this review- buy it now.