I like this mode better honestly. Much faster paced and really fun.
So as you can tell, Riku's gameplay is much more streamlined than Sora's. He's quite a bit faster, has only a small handful of Sleights (which can only be used in Dark Mode - more on that in a second) and instead of deck capacity upgrades he just gets straight-up damage boosts. His decks are also fixed depending on the world you're in, so the whole deck management and capacity element is out. His reloads are also instantaneous, which means Maleficent's card is just a straight-up attack boost with no downside.
Dark Mode works similarly to something like Devil May Cry's Devil Trigger - while it's active Riku gets faster, does more damage and his dodge gets massively upgraded and covers nearly 2/3 of the arena. This is also the only time he can use his Sleights. To activate Dark Mode, you need to break enemy cards - the bigger the difference in the values, the more Dark Points get added to your total, and once it hits a high enough value it will activate when you play one more card. If your DP drops too low while you're in Dark Mode you'll drop out of it, though, so don't get reckless and let your cards get broken too much.
