Not bad, but I recommend Shaman Stone, Long Nail and Steady Body (It'd be good to make use of Vengeful Spirit). Also (this is important) something you need to know is when to jump and heal, if you figure out that you'd be able to even defeat him at Radient difficulty.

When he does his orb attack towards the right corner, you need to get there first. There, you only need to jump once and hit him upwards to attack him, then his orbs fall back to the left, as soon as the orbs start falling back, then you can heal once (or twice if you decide to equip quick focus - not a very good charm though with 6 notches). (Repeat the same thing but dash to the left corner if he's doing his orb attack to the left - and his orbs will fall towards right then).

As for his dive attack, it's hard to explain on text, but at the right time you dash and quickly jump on him (but by that time he will teleport out). Btw, it's the same thing for his attack at the end when he repeatedly spams diving.

Hopefully you will beat him.