Saïx

Saïx, the Luna Diviner, is the 7th member of Organization XIII, and the fourth boss in The World That Never Was. He also has a data version at the top of Pride Rock in the Pride Lands that is significantly more difficult.

Berserk

Saïx has a unique mechanic called the "Berserk" gauge. As he calls on Kingdom Hearts' power, the guage will fill, and once it is full, he enters his Berserk State. While he is in this state his moveset changes and he will often throw his Claymore at Sora. To get him out of this state, use the reaction command to pick up his dropped claymore. Then, between his attacks, run up next to him and repeatedly attack him with it. This fully deplete the guage and returns him to his normal state.

Using Reflect

Saïx is particularly vulnerable to Reflect while he is not in the Berserk State. If he attacks Sora and is reflected enough times, he will drop his claymore and become vulnerable for one or two combos. After the combos, he will usually retaliate with a dash attack that can also be reflected. If Sora reflects this dash while in the corner of the room, Saïx will still be in range of the reflect damage after the dash.

Peter Pan Stunlock

The easiest way to deal with Saïx is the Peter Pan Stunlock. This is fairly straightforward; however, you need to get him out of his Berserk State before performing it. Once you have begun performing the stunlock, he should not escape, even if his berserk gauge fills. Once he is low on health, use a finisher to end the fight.

Double Negative Combo Stunlock

If Peter Pan is not an option and you have two Negative Combo abilities that can be equipped at once, you can use the Double Negative Combo Stunlock instead. Like the Peter Pan strategy, you will need to get Saïx out of his Berserk State before performing the stunlock. As before, he should not escape the stunlock even if his berserk gauge fills.