The problem with suing God
I suppose is one of lack of jurisdiction. Although God clearly ceded worldly dominion to humanity[1], to actually bring a successful suit against the deity I suppose one would have to make a strong case for representing all of humanity rather than one small faction or a subdivision thereof.
Thus, the plan:
1) Unified world government
2) Sue God
[1]Genesis 1:26-28
(posting prompted by this article on a climate change lawsuit)