Chronic Logic

I had the same problem in 7. I've also got a Nvidia card so it may be related to that. (I can get more specific specs later but I'm not at that machine right now.)

I was thinking limit the AI to a certain number of points on the field at once. (Is there some kind of limit.)
Also, if limiting actions is too much, then limit the number of units that can be activated on a given turn.

On the subject of connection lagging, can we have a game log? When the AI's going there's a list in the side panel of what happens, why not leave it up when the panel's not being used for a unit or the castle? Sometimes the connection lags and suddenly pieces are all over the map and stuff is dead and I don't know what happened.

What kind of builds do you use against the AI (aside from the hydra)? Which seem to work the best?
I've played against the AI for the last 10 levels (at 58) with 5 rangers which has proved quite effective except when there are 3 or 4 heretics. (Or when the AI starts spamming heavies.)

If you read the description of the Magus' spirit form (inside a game) it says the spirit is only supposed to last two turns.
I can't be more specific right now since the AI hasn't used one against me today.