Dodge roll...i know it might sound stupid but let me explain
When anyboss or some heartless is about to attack, simply dodge roll, and u will not get hit, no matter what, i think its like a glitch or somethin cause like say u are facing marluxia and he uses that giant petal shower attack, u can run around all u want but u will still get hit, but if u use dodge roll at the right time u dont get hit, also for dark firaga that riku replica uses, if u dodge roll twards it, it wont hit u, this is true with any attack really, like axel's "undodgeable" fire wall, if u dodge roll through it then u dont get hurt, this saves 0 cards for more powerful attacks that bosses use that do multiple damage that cant be dodged easily, therefor making it easyer, dont believe me? try it out yourself next time u fight a boss xD
When anyboss or some heartless is about to attack, simply dodge roll, and u will not get hit, no matter what, i think its like a glitch or somethin cause like say u are facing marluxia and he uses that giant petal shower attack, u can run around all u want but u will still get hit, but if u use dodge roll at the right time u dont get hit, also for dark firaga that riku replica uses, if u dodge roll twards it, it wont hit u, this is true with any attack really, like axel's "undodgeable" fire wall, if u dodge roll through it then u dont get hurt, this saves 0 cards for more powerful attacks that bosses use that do multiple damage that cant be dodged easily, therefor making it easyer, dont believe me? try it out yourself next time u fight a boss xD