Click HERE to see this thread with all of the graphics, features, and links.

There can be all forms of Metroids, even the one's that were defeated. The floods can have all forms as well, but here's the catch, each side will have 500, so 500 Metroids and 500 floods. Who shall win?! Let the battle begin!!!

When Metroids eat X-Parasites for breakfast (who better infect/mimic others and reproduce faster than Flood typically do), what makes you think the Flood would stand any real chance against them? Since you said all forms, Fission (or any Phazon-evolved ones) and Omega Metroids stomp, especially if there's even one Queen alongside them. This be spite.

Yes, but remember that the flood really are a threat, with their Gravemind, Metroids could have a problem. But I agree, you've gotta good point, and yes, there can be the Metroid Queen. Btw, I'm not taking sides... yet.

The Gravemind can use strategy, but it might be a bit difficult when none of his troops can even hurt the enemy. Maybe they could kill the Tallon Metroids, but Zebes and SR388 Metroids won't go down to Flood in melee.

The smaller Metroids fight by draining lifeforce, right? Flood combat forms do not have any lifeforce though, they are reanimated corpses more or less. So, the small Metroids would go down in machine gun and Plasma fire.
And I am fairly certain that the big Metroids are prone to infection by swarms of small Floods.

Yes, Metroids are implied to drain life energy. I don't think that would actually have any impact here, though, since Flood aren't actually dead. They use corpses, but individual Flood are still living creatures that are more than vulnerable to Metroid attacks, Pure Flood especially.

As for Machineguns, even small Metroids are too durable for that. Plasma will work on a Tallon or Phazon Metroid, but anything bigger than that is practically immune. Where are the Flood getting these weapons, though?

On Flood infections, I highly doubt it. Metroids were built to be immune to X infection, and absorb said X on contact. The X are much better than the Flood at the whole infection thing, work on a smaller scale, and don't require calcium to work. Attempting to infect a Metroid is guaranteed to end badly for the Flood.