: That reminds me that I've always found it an interesting leap in regards to
: the Delta Halo situation where we leave it in Ghosts of Onyx, and then it
: showing up as a Flood hive in Halo 3. We know the Covenant were apparently
: fairly effective in stopping the Flood from leaving the Halo ring—but
: leaving High Charity would have been a fairly big oversight. Did they
: attempt to destroy High Charity to stop its infestation?

The civil war was still raging when the In Amber Clad jumped into the interior of High Charity. The station's defenses would have been running at max, and the Gravemind would have tried to keep them intact and running. There's a small question as to how they were powered after the Dreadnought left, but I would patch that plot hole by saying High Charity's power requirements had long since grown beyond what the Prophets could safely siphon off the Dreadnought's engine, and additional power stations were installed.

So... the best energy shielding and starship weapons the Covenant can build directed by a hyperintelligent fungus older than the known universe, versus a fleet of lesser vehicles damaged by battle and divided by factional strife? My money is on High Charity.