I was discussing this battle with my best friend before who is a pretty big Slade fan, and we thought that this battle would be damned good. They are both supposedly the greatest Assassins within there respective worlds.
Slade has gotten into it with superman.
While Gamora has gone at it with Drax the Destroyer.
Gender: Male Location: Drinking gasoline. Pissing napalm.
Gamora: much stronger, as fast or faster, better MA, better healing factor, with a weapon capable of slaying gods. She probably takes a clean sweep, although I don't necessarily think Slade makes it easy on her. He's very smart and can read moves. Just don't think thats enough.
Gender: Male Location: Drinking gasoline. Pissing napalm.
I don't see grenades being effective against Gamora. She's taken out an entire army by herself, tanks included. His Prometheum sword would definitely cut her, if it hit. But as noted, she's got an insane HF. On par with Classic Wolverine. And she's extremely fast and agile. All's it would take is one strike from her Godslayer to end it.