Superman as in Pre Crisis
Spawn as in King of Hell
Now the Twist. Since Spawn can stop time It wouldnt be fair. Since Superman can move near Speed of Light isnt fair either.
So Spawn can only Slow Time (Lightspeed Supes to Hypersonic Supes) in his City wide bubble. Also Supes has 2 Holy Super Brass Knuckles!
With the field even a bit who wins?