Ozai vs. Unalaq

Setting: Earth Kingdom, near ocean.

Who would win in a battle to the death?
Waterbender vs. Firebender ( no sozins comet)

If we're using Avatar Unalaq, Ozai's screwed without the comet's assistance.

Yeah, no Dark Avatar Unalaq & no Sozins comet.

I'd say Ozai only because of lightning bending.