The Force’s Speed is reduced to 0. The Force targets a number of enemy Forces with total combined Effective Combat Strength less than the Force’s ECS, that are within the same Region as the Force, and that are benefitting from the Fortify effect.
The target(s) cannot use the Skirmish, March, Conscript, Rampage, or Resupply Actions until the the Force stops besieging its target(s).
Until the Force stops besieging its target(s), the Force gains a +50% Combat Strength Multiplier when defending against attacks by any of the besieged forces. This effect does not stack with itself.
Until the Force stops besieging its targets, the Force gains a +20% Combat Strength Multiplier bonus when attacking any of the besieged forces. This effect can stack with itself if the Force uses the Besiege Action multiple times.