The art in this game is amazing. Lots of bright, vivid colors make each of the areas in the game memorable. The music (and the ambient background audio) are also very good.
There are two types of battle outcomes in this game; the times when you barely survive with a single hit point left, and the ones where you obliterate dozens of enemies while hardly taking a hit. In both cases you feel like a badass. The combat is very fluid and the guns complement the swordplay. The upgrade system is also nice, as it allows you to customize your character to your personal play style. I preferred the pistol and shotgun.
When not in combat you'll be exploring four different areas, one for each cardinal direction. Each area feels very different from the others, both in its visuals and in the enemies you face. There are several different paths to take, and many hidden secret areas with health pickups and tokens used to upgrade weapons. This rewards exploration, since you'll want to get as many tokens as you can to upgrade your gear.
Each of the areas also has a boss. What I really liked was that each of the different enemy types in each area had attacks and behavior that, if mastered, prepare you for fighting the boss. The bosses are definitely challenging, but just the right level of difficult. You will be brutally punished for button mashing. You must take your time and study the movement and attack patterns before you begin to assemble an attack strategy.
The west boss was savagely difficult. After the first thirty attempts I gave up. I came back later with some upgrades, and it took another twenty attempts. The other bosses weren't as hard, at least for me. I was able to beat the north and east bosses in around four attempts each, and the south boss on my second try. The final boss was easier than the west boss, taking around fifteen attempts. Obviously this will vary according to the player, with some dismissing it as overly hard. Honestly, I think the difficulty is just right. I found it to be an order of magnitude easier than Dark Souls, for example.
One annoyance I had throughout the game was that many of the secret areas aren't easily visible (obviously hidden areas are, by definition, not visible). What I mean is, there were absolutely NO clues whatsoever, subtle or otherwise, to indicate the presence of a majority of the secret areas. This lead to hugging the wall of every room after I'd cleared it of enemies, just to be sure I hadn't missed an invisible passage. Just when I'd start to consider giving up this obsessive search behavior, I would find yet another completely invisible passage way, which I'd never have found any other way. That took away some of the "organic" pleasure in finding the secrets, making it instead a very mechanical process.
I also fell off the map countless times because I couldn't see what was on the screen. Sometimes it was because of the lack of depth perception in some areas; others it was because my character was obstructed from my view while I searched the edges for hidden passageways. This was particularly annoying, because falling off the map costs a full hit point.
Another minor complaint is the lack of explanation concerning how to open blocked locked doors. When approaching one of these doors, a HUD element pops up showing the number of triangles you have. Because this UI element is so prominent, I didn't look close enough at the physical door. It turns out that the door itself shows you the number of triangles required, not the panel. I ended up thinking several of the doors were broken, because I had four triangles, which filled in the UI element completely, but the door itself actually required eight. A simple UI text label with "Two more required." would have been sufficient.
Finally, I ran into one technical issue that made it nearly impossible to play the Steam version of the game on Windows; the game would rarely launch. Twenty to thirty launch attempts would be needed before the game would successfully start; sometimes even a reboot wouldn't help. The game ran fine on my MacBook, however, so the obvious and simple solution would be to transfer the save file...or so you'd think. Unfortunately, the game encodes unique data into the save that prevents you from copying a save file to a different machine. From what I can tell, the developer didn't do this on purpose; it's how the underlying engine (GameMaker) writes its save data.
Anyway, to deal with the issue, I ended up having to write my own tool so I could transfer the save onto a Mac, where I was able to finish the game. Because of this problem, I would recommend sticking to a console version for this particular game.