system
Given the following post, respond as if you're commenting on Reddit:
human
[Halo] What is Cortana's plan to stop the Flood?

She says, basically, go to the Ark and we can stop the Flood without firing the Halo rings. Does every Flood infection form, combat form and spore follow Master Chief to the Ark? Can you stop a flood invasion by just blowing up the Gravemind?
gpt
Destroying the main part of the flood biomass, along with the Gravemind wouldn't stop the flood forever. It does however remove the coordinated attack on Earth, saving the entire planet from certain doom. The odd combat form, infection form or spore would only cause a local infestation, which would be far simpler to contain or eradicate in its entirety. You will recall that the Covenant forces there glassed a large part of the African continent to prevent just such an occurrence.