What you get is an exploration game, with an upgrade system (the equivalent of leveling up in an RPG, except more satisfying), and a reflex-driven 2D shooter (or pattern memorization shooter). And is the game difficult? Not on regular difficulty. But after beating the game, a hard mode is unlocked which proves to be a bit more satisfying for those looking for a challenge. This is a solid game. Though that being said, there is a good counter-review by Viscount on Gamefaqs.com where he probes into the games more subtle weaknesses, which he argues plagues too many games at large in the modern era.