I never really had any problems pulling off artes, unless you count the five minutes I accidentally spent in full auto mode.
Just make sure you have a full CC gauge before attacking. Mashing X with only one or two CC won't pull off any combos, and you wont expand your max CC either. Oh, and don't forget to dodge and charge your guards either, both are pretty key from what I've played.
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SunnyX ~ The cream of Robopon fanboyisim
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