[quote=Sep]I'm a little worried about the Mac Cannon but with the fact it is a ship killer not a planet killer it isn't too bad.[/quote]

They used to high gigaton yields, but not anymore. UNSC firepower is for shit quite frankly. So nothing to worry about particularly.

[quote=Sep]Rather than have it offline like the planetkiller weapons I may make it so you have severely depleted ammo reserves for it.[/quote]

I honestly do not recall planet killer tech except in the hands of elder races.