Terrible AI ruins what would otherwise be a fun game. Selecting hard just means terrible AI with more HP (i.e. cheat)
Even with this grossly unbalanced play, your AI opponents will not comprehend that in a take and hold flag mission, they need to take and hold the flags. Your opponents will be 3 ~ 4 levels over your team, and have a 6 to 1 kill ratio, but still loose since they did not take and hold flags.
Multiplayer is just as frustrating, as you will be constantly screaming at your AI allies to do something, anything to aid your cause. That is when you can find your allies, since they seem to disappear from the game at times and leave you to believe that you are fighting alone. When you do occasionally run across a computer allies, then are normally just standing around, and have no concept of team play. Low on health, running from an opponent who is down to 50% health and out of mana; no worries, the AI will just stand and watch you die. No reason for the AI to try and help, or get an easy kill.
It is a shame, since this game had real potential, but until the AI is fixed there is just no way to recommend this game.