A good idea and story, ruined
You're a guy who wields 7 different swords and hacks hundreds of enemies down during a quest for a golden dragon.
The game is kind of a mixture of hack-n-slash, survival horror and platformer.
Now if I told you all the smaller aspects of the game, you might think "great, I need to play it" but all the great ideas are completely ruined.
The story is quite interesting, and would make a great movie, but the gameplay just ruins the fun. You'll probably lose your interest in the first few levels, which really is sad. I've never seen such a great story wasted so badly with a horrible gameplay like this.
Now I'd enjoy playing a good hack'n'slash game with hundreds of stupid goons coming at me, but the whole fighting engine is crap. It feels like walking in tar in some places, and there isn't much difference between attacks, even if you do get 7 (or 8) different swords. Some are faster to use, some do more damage in one hit, but they're all the same: boring. You walk around, pressing the same button trough every level.
Although the swords have special abilities, those abilities suck. One weapon can deflect attacks but is useless when there's more than 4 guys coming at you, and you'll get hit after the shield animation ends.
Another sword works like a propeller and gives you the possibility to leap longer distances, but is only useful in places like a big cave with multiple levels and huge gaps between narrow ledges (and that level SUCKS, btw).
Only really useful sword is a sword you can throw around like a boomerang, but it does the least damage and it takes time for the sword to come back if you miss when there's ten guys around. So although the special stuff sounds interesting, there's not that many places where you can actually use them, since the levels are quite...simple.
Gokuraku (the main character) can also unleash some kind of a super attack after lots of hacking, but I never really used it that much, it takes time to load up and is, again, quite useless.
The basic idea of the levels and enemies is very interesting and gives you the feeling that you're really on an adventure. You start out in a training level in bright daylight, fighting normal bounty hunters that are very much human.
Soon, you're stranded on a strange island filled with bloodthirsty, mindless freaks during night-time, all alone, with one broken sword. Cheer up, it only gets worse from that.
You'll meet interesting people, fight strange creatures and occasionally you might think you're safe. That's until your friends die, night falls and more ninjas come at you. It's a roller-coaster ride, and fun.
If you're dead tired of Gokuraku and his swords, you can also play the part of his female companion Oyuri, who carries GUNS. I enjoyed her side of the quest most, since the story for her is a bit better and the guns handle way better than swords. Just point and shoot, not need to get all up-close and personal. The story is the same, but you'll see what happened to Oyuri after she and Gokuraku-Maru got separated. Now if you do play Gokuraku's story trough, you absolutely NEED to see Oyuri's side to understand everything because their paths cross so many times in strange ways.
If you just play Gokuraku's part, you'll be wondering why Oyuri's gun is abandoned in a pile of rocks, why you see her crying all alone in a haunted house and why she later comes and saves you in a boss battle.
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SPOILERS FOR OYURI'S STORY:
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After the shipwreck, Oyuri wakes up in a kitchen, where a guy is going to cut her in pieces. Before he strikes, 3 bounty hunters she fought in the beginning come and save her. They release her and she needs to fight a horde off crazy people and find her gun, Kittykat. Soon, she and her bounty hunter friends find themselves in a field with odd-looking scarecrows. Endless amount of crows try to kill Oyuri, but by following the trail of scarecrows (that are really alive) she gets past the crows.
After a bunch of tiresome battles and boss battles, sometimes armed with just the black powder that does extremely little damage and hits only things right next to you, Oyuri and friends (a little girl saved from a pile of bodies joins her) make it to a nice looking mansion. The owner is a maniac, and everyone in there tries to kill Oyuri. She needs to find a gun, and after slaughtering masses of people, fighting a freaky bossbattle with a lunatic and his 100 miniature clones in a bathroom with a bathtub full of acid and locating a key behind a picture on the wall, she faces the boss of this mansion in a dance hall. One bounty hunter is lost (my favourite one *sob*), and every enemy around is scared of Oyuri and her gang (or maybe something else...hmmm...). Soon, she's in a haunted theatre. One bounty hunter becomes possessed, little girl with a green-glowing medallion goes missing and Oyuri wakes up from a nightmare. She meets a strange, teleportating mirror-ninja, and gets thrown into a well by the little girl. In the well, another woman turns into a freaky snake and Oyuri realizes she's in a hellish cave full of creatures.
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END SPOILERS
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Like I said in the beginning, 7 Blades is a mixture of different genres.
The basic idea is slashing people down like hay, but the overall feeling is like a horror movie. You'll also encounter platforming in some levels, although those levels suck the most because the jumping is just like the fighting in this game: horrible.
Story is really great, one of the best I've ever seen.
7 Blades totally sucks as a game, but seeing the story could be worth it all.
In case you do get/have 7 Blades, don't pay that much to the faqs here on Gamefaqs/Gamespot: They are filled with mistakes, and some of them are obviously written by a guy who never understood what he was doing. Following one walktrough might spoil some of the fun, so only check one if you're in a trouble of finding a lost key or something.