Zor Vs Shuma-Gorath

Zor in his prime.

http://www.comicvine.com/zor/29-49562/

Shuma Gorath

Any reasons?

Shuma Gorath is a multiversal level threat.
Something that can not be said to Zor.

Zor is pretty much up there, comparable to Kang or classic Synnar..
But not Elder God-level cosmics such as Shuma Gorath.

Zor has fought Spectre, dude. Pre-Crisis Spectre, IIRC. So it's a good fight.

Spectre's power level constantly fluctuates.

One instance you see him beating Koth Shoggoth (Shuma Gorath counterpart), in another he get's punked by BA.

Zor beating Spectre, is like Spidey beating Firelord or BP beating SS.. pure CIS

In his prime, full power, Zor IS high end Spectre.

Okay. If that's how you see it.

Well, how high do you think Spectre was here? Spectre sends Zor out of the atmosphere. Throwing comets at each other.

http://mightybroke.com/7soldiers/zatanna/7sz04.htm