This level is infamous. Equip the Reflector and Wonder Coat. They aren’t required, but they will help. You are poisoned, so your health constantly decreases and health is sparse. The first two waves are just straight-firing stars. Holding the left stick + X will produce large sweeping attacks that swipe these stars back at the enemies. The third wave has enemies that fire homing stars once they get close to you and jump. Run to a corner and block everything you can. Charge them a bit to force them to jump, and use chi moves to take them out quickly.
There is a restart point at the solo teal assassin. Focus her down quickly; drop a fast tornado kick when he turns red during your combo. She dizzies easily and has lowish health. The white assassins only do a jump kick, so they’re relatively painless. One dragon kick kills them. When the screen fills with enemies of each variety, summon some help. Loh’s Guards don’t do a whole lot, but they have high HP for their extremely low cost. They will take away most of the fire while you can focus down the teal assassin.