So sad...
Theres no true fans of Symbiotes left... Well here I am...
Venom is powerful... Hes hella powerful... Infact, everytime he fights with Spiderman, he wins. There hasnt been one time where spiderman has actually won like Venom has... Venom has held down spiderman by the face and knocked the crap out of him.
Carnage, however, is alot faster, much more immune to damage, but hes more stupid and less intelligent. Venom cannot take down Carnage alone, however, he has tried, and he almost has, but he's never managed to take the final step... I quote how pissed off venom gets around carnage...
Carnage - "Yo... Pop, what are you doing here?"
Venom - "For every drop of innocent blood you have spilled... I shall take a gallon of yours!"
Eddie Brock is a peak human muscularity. He cannot get any stronger basically, he can lift about 800 pounds even without the symbiote up. Hes extremely buff, he knows alot of fighting techniques, and he has experience carnage lacks since Cleetus Cassidy is insane (the guy inside carnage)
When the symbiote is up... Eddie Brock becomes Venom.
Venom is capable of resisting medium round fire, lifting near 80 tons, firing webbing stronger even than Spidermans, shape shifting hands into weaponry, tendriling (shooting long tendrils of the suit into say, someones ear and killing their brain), and several other special abilities which include turning off spidermans spider-sense and wall climbing.
Given the correct circumstances, it is possible for Venom to beat Carnage, but at this point, the closest hes got is taking him down on the ground, Carnage is just to crazy, to reckless, and because Venom isnt as reckless, he doesnt have many options.
Plus, Carnage normally threatens killing more Innocents, and thats when Venom is torn seeing as how he basically lives to protect, which is why every time he gets close to finally killing Spiderman, he stops because he realizes Spiderman is required to protect as well, which, contrary to popular belief, shows that Venom is not even close to being a Villain, but is infact a misunderstood Hero.