monkey289 wrote:
I think that having the second series might be enough? Not sure, though, how much more damage does it do to a normal attack?
No. Having the second series will not be enough. That's like you using Illusion Chain when you're L80, because you think that Heaven Chain isn't necessary. You either get it all, or you don't get it at all. By the time you're L80, the damage of your normal attack may even surpass that of the second book. So if you plan on using it, make sure that you farm enough SP to get it all.
Not exactly sure what your second question means. If I interpret it correctly, you're asking how much more it does than a normal attack.
For me, I do about 500 a swipe on PEGs. Times two, because there are two swipes, equals about 1000 damage. With Crosswise Smash, I'm hitting about 1100 per swipe, and since Crosswise is the 3rd book, there are two swipes, giving a total of around 2200 damage. So yes, it's quite alot more effective than a normal attack - and good for such a low MP usage.