Dynasty Warriors 6 was pretty bad, while Dynasty Warriors 7 is probably the best the series has been in years. The story mode is leagues above where it used to be, and even somewhat captures the feeling of the novel at moments. I'm a big fan of both the novel and the actual history, so the improved story mode was amazing for me.
The gameplay is really polished and the ability to swap between two weapons and essentially use any weapon is a great addition. Don't listen to those that say the ability to use other weapons is a bad thing. Their argument is that it makes all characters the same...well no s*** if you decide to use the same weapon with every single character. Each character has a weapon type that they have a special affinity with (default weapon) and they get an EX move (usually mashing on the Y/Triangle button a few more times after a charge attack) with that weapon. Generally the character's EX move is something unique that you might want to use often. I stick with keeping the default original weapon type with every character and often have a trump card of a really good weapon or a fun one. That being said some characters are better with certain weapons, but you can almost ignore that since you can learn skills that automatically max your proficiency with a given weapon type.
I've played just about every musou/warriors game and Dynasty Warriors 7 is one of my favorites. If you loved 4, I could easily see you loving 7. On top of that you'll have fun getting used to quite a few new characters and even a new kingdom faction.
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