Castlevania appeared in Mushroom Kingdom. Help Mario explore the castle and stop whoever is behind this.

Features:
-mix of Castlevania and Mario
-huge, exploreable world with map
-experience and equipment system, along with magic skills to upgrade
-enemy encyclopedia
-several abilities you need for Mario to reach new areas
-100+ old and new enemies
-great soundtrack
-many secrets
-runs on Windows, Linux and Mac!