In the Old Testament, God often descends and physically defeats the Jews' opponents. Are there any pagan sources that mention their Gods descending and defeating the Jews?

I'm not really sure the Old Testament does have God descending physically to defeat the Jews' opponents, which would make comparison difficult. If we're going to compare like-to-like, I would ask you what Old Testament passages you are thinking of? Then we can discuss what sort of interference other Gods offer their people in non Judeo-Christian texts.