So how does this work?
The map is divided into regions. Some regions are worth Victory points. At the start both sides have the same number of VPs.
There are three rounds. In each round there will be a number of 40K games determined by the number of players (if there are 12 40k players thats 6 games). For each game of 40k in each round, the Chaos player group/leader rolls off against the Imperium (+1 to roll for current winner on VPs, chaos get +1 at the start) for each game (6 roll-offs in the example). After each roll the winner of the rolloff decides a region to attack from and an enemy region to attack. He places an arrow on the map to indicate this. This is then repeated for the other games. NB - there will be time to "plan" strategy before the roll-offs.
You aren't allowed to place an arrow between two regions already indicated for a battle, otherwise any arrow combination is allowed. You can place more than one arrow into the same enemy region (pincer move!) from different attacking regions.
Each arrow then represents the battles. The winner of the battle takes the region at stake (if the attacker loses he loses the region he came from). Clearly its better to attack from low value regions into high value ones! Draws are won by the player with the initiative (chaos at the beginning).
VPs decide the campaign result. In addition to VPs gained for regions games themselves may yield VPs for destroyed enemy forces. Consult the chart called "roll to destroy". A big win is more likely to yield extra VPs in this way.
At the start the Chaos force is already invading when the Imperium arrive. The first gothic game will be a "surprise attack" by the Imperium. The winner of this game will be allowed one bombardment in the second round in a game of his chosing (see master of ordnance in Imperial Guard Codex).
They will keep this if no more gothic games are played. If a subsequent game is played in the second round they should be convoy - the side which lost the first gothic game being the convoyer - then in the final 40k games the winner will be allowed to "re-cycle" one non HQ unit in one game in the third round.
In addition gothic games are worth 20VPs each.
Gothic games in the final round will yield 20VPs to the winner.
The winner of any AI games (overall) in round one will either be allowed a ground attack or have the effect of Master of the fleet for one game in round 2.
Ground attack: Each turn the player may use his HQ to order a ground attack. If a Ld test is passed the attack will occur just before the opponents shooting phase. Bombs (an always scatters battlecannon shot) or Napalm (hellhound attack - scatters - pointy end points to a point in own deployment zone). Place the template on an enemy unit (max models) and scatter 2D6. The enemy may attempt to drive the enemy off instead of shooting that turn. The plane counts as 12 inches away, T6 and 6s to hit. Any "wounds" drive off the aircraft and the attack has no effect.
If no subsequent games are played this effect continues in round 3. Subsequent games in round 2 have the same effect on 40K games in round 3 for the winner.
Games of AI in all rounds count for 10VPs per win.