I think God and Satan are symbolic of lightness and darkness...good vs bad....body vs soul...seen vs unseen... yin and yang. They could also be symbolic of emotions...love vs hate...happy vs sad...charitable vs selfish...trust vs suspicion...blame vs forgiveness,...etc. Also, war vs peace, famine vs plenty, disease vs healthy, etc.
If God rules over the spirit then Satan rules over the flesh. In Hindu, God would be the crown chakra of enlightment located at the top of the spine near the brain...and Satan would be the root chakra of bodily awareness .located at the bottom of the spine near the anus...which is as low as it gets. So if I had to guess what Satan wanted it would be darkness, ignorance, hate, greed, insecurity, pain, sickness, filth, war, famine, suffering, etc.......and of course God would want the opposite.