i can't beat riku i think the 3rd time its after beat the darkside so is there a way to beat him or what lvl i should be or something

u mean when you are with riku yourself? th ewhole gameplay with riku is pretty easy but when u meet replicu the 3rd time it is i think he is pretty heavy, i also haven´t beaten him yet.

well for Sora I was level i think 45 and just go in with a normal deck with at least five 0's and DO NOT use them as the first when you use a sleight... and Riku it just depends on what level you are... fixed decks suck...

Well, You have to be at least lvl 47 and have around 5-6 zero cards in your deck. If you're on Riku's Story have at least 15 ap and 17 dp.
Strategy: Only use the zero cards when the riku replica uses dark aura.
When he uses dark firaga just dodge roll (push left or right twice in a row).
Heal only when he reloads or he will just break your card with a zero or a sleight.