This god exists outside the usual D&D patheon, belonging instead of the group of optional gods used in the Sandstorm setting. Even though I haven't illustrated any creatures from Sandstorm for this blog, it's probably my favourite setting; I really love deserts. There's just something about long stretches of arid, lifeless, deadly nothing with small settlements trying to survive that I find incredibly interesting.
And out of all the gods listed for Sandstorm, I think Azul is the most fascinating. I like the idea of a god whose domains include Water and Plant, and who farmers and travellers rely so heavily on, should be such a petty, selfish god who demands the life of something (usually an animal, but will take a sentient creature) in exchange for his life-sustaining services. Using ironic sacrifice. I'm not sure whether he has a rivalry with Solanil and Tem-Et-Tu (goddesses of oases and rivers, respectively), or whether they're also afraid of offending him because if he stops raining, their own domains would dry up.
It's always something I like in mythology. A god that's worshipping it isn't so much as admiring it as much as it is begging it not to hurt you.