is the diagram I have drawn for this mode.
So, the objective of this gamemode is to eliminate both enemy teams by breaking them, and eliminating their heroes. To break a team, their morale must be reduced from 1000 to 0.
The top and bottom lanes of each home base are guarded by two archer towers which can be destroyed to permanently reduce the morale and maximum morale of their team by 150 points, as well as make it more difficult for them to capture that minion point by allowing your minions to push further into the lane. Destroying a tower grants your team 75 bonus morale. Three minions are as effective at destroying a tower as one hero, and the archer towers will prioritize enemy heroes over minions.
Controlling a point will grant your team 1 morale every other tick, while reducing the other team's morale by 2 every tick. For example, if point A is controlled by team 1, team 2 will lose 2 morale each tick, while team 1 will gain 1 morale every other tick. If team 3 managed to control that point by directing minions through the central point (a bit of the graphic I forgot to add), both team 1 and 2 would lose 2 morale per tick, and team 3 would gain 1 morale every tick. Capturing a point that your base is not connected to would be very difficult to manage, as it would require a lot of minion wave babysitting to direct them through the central point. This final bit could always be scrapped, as it might be too tricky to implement.
The central control point functions as a standard A or C point does in Dominion mode, and controlling it grants 1 favor every tick to the team controlling it, and 2 favor every tick when a hero is standing in it.
For every minion kill a hero scores, they have a 20% chance of gaining 1 morale. For every hero kill a hero scores, they gain 5 morale, and remove 10 morale from that team. Executions double the morale removal and gain from a hero kill. Double kills restore 10 morale, triple kills restore 25, and quadrakills restore 35. Team kills reduce the morale of the team by 20 on top of their kill values.
When the first team is eliminated, they are permitted to leave the match if they wish without forfeiting their match rewards or their reinforcements.
The team who wins a Siege will be given a slightly larger number of reinforcements (perhaps 10% more) than in any other game mode. This may be scrapped in case of overpoweredness.