Frankly...
...I think the general populace has to get some skills.
1. With the normal sword, you should never see that third slash in combat. The slash that leaves you open to attack should never be seen. Try this: Slash+Slash+upslash+downslash+downsla sh+upslash+then keep spamming the slash while they're on the wall.
2. Can't beat the 1st level? On MORTAL mode? Here's a tip. SPAM THE UZI. Once the guys with the bombs on there backs come out, the sword won't work so good anymore, so just keep bashing the S button. Charge and spam the uzi throughout the rest of the fight and you'll do fine. Enemy comein' up on ya? Invadin' your personal space? Either dodge (tutorial to learn how to), or jump off the wall.
Of course, if you can't even get to the bomb guys, refer to the first line of this review.
3."...bitchin' about difficulty..."? I tire very fast when people want to take hardcore difficulty games and change them to casual. If there is a hard game, try not to let the tears stream from your eyes. Try to beat it without B., whining and moaning about how hard it is. Some games are gonna be harder than others. Deal with it.
Of course, this is typing as if you didn't run into any game ending glitches, i.e. sinking through the floor and instantly losing or game not advancing.
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I'd have to say the game gets about 3.5 out of 5 from me. Not perfect, but it definitely doesn't suck.
-I actually liked the controls personally, and it gives you the option to change the controls anyway.
-News flash, this is not Devil May Cry. It's a FLASH game modelled after it. It takes some(a lot) of pointers from the game, but it's totally different. Heck, the guy said in the Author Comments that it was gonna be hard.
-I didn't really use the upgrades that much, so I can't really testify about them :P
-Not a lot out of the main game of fighting was really notable. I didn't really pay any attention to the storyline. Sorry :(
But the game was still fun (for me) and provided a challenge. For that I give it a...
3.5 OUT OF 5
(Possibly my first half grade review. I'm just gonna round it up and vote 4. Looks like you tried hard, but you can never try too hard! Unless you die. Then yea, you kinda tried too hard, lol :P)