Mfw "we can take the flood"
No, you can't.
It would be asking too much for anyone to do a bit of research before they spout misinformation, wouldn't it?
I don't see why Oryx couldn't Take Flood?
The Flood couldn't beat the Hive any ways. Without Forerunner technology they have no way of actually getting into the Hive Ascendant Realm. Even if they do get in, they can obly wage a war of attrition for so long until the Deathsingers close the way in. Unless the Gravemind understands Sword Logic the Hive are not beatable. It took the Quria, a Vex mind linked to thousands of planets like Mercury full of processing power, a considerable amount of time to deduce Sword Logic.
If the Hive don't have Oryx and the Ability to Take, and the Flood gain a decent amount of biomass before they meet, I will give it to the Flood, but the hard truth is that nothing in the Halo-verse with the exception of a BFR victory can stop Oryx and his Taken.
We don't know if they can take the flood. So it's speculation. There are no facts when it comes to one enemy fighting an enemy from the universe because we don't know how the two interact. For all we know, the hive could be immune. Maybe they aren't.