An assault is an attempt by infantry to storm and capture a fortified city. Given a significant advantage in land technology, leadership and/or numbers, an assault can substantially shorten the time necessary to capture a city.
For discussion of how to use assaults, see the article on assault strategy.
Initiating an assault
An assault may be started against a fortress whenever a number of conditions hold:
- Enough friendly troops must be present to siege the fortress
- At least some of those troops must be infantry or artillery and must be owned by the country initiating the assault.
- The weighted average of morale for all troops in place at the siege must be "disciplined" at minimum (green morale bar at minimum 1.500).
- The country or player initiating the assault must be in control of the siege.
- A country must have land tech 5 to start an assault. Note that lower-tech allied infantry can help; they just cannot start the assault.
The AI will start assaults when it thinks its chance is good. Its algorithm takes account of armies in adjacent provinces that might move in to start a battle, but not other armies in any other provinces.
For the player to initiate assault, he must select one of his armies present at the siege which has at least some infantry or artillery, and press the "Assault" button on the siege screen.
For purposes of combat resolution, the side that initiated the assault is the attacker. All non-moving land units in the province which are enemies of the country controlling the fort are automatically added into the attacking force. The defending force is a siege defender force, which is initialized when the siege started. Note that this force can be attrited via siege advancement before the assault starts. Earlier assaults may also reduce the defenders of the fort.
Effects of assault
When land units are engaged in an assault, they are completely out of your control. You cannot give them any orders of any kind.
Sieges are suspended by assaults. If a siege advancement day happens, it is simply skipped for that month with no effect.
All land units which enter and stop in the province when there is an ongoing assault automatically get added to the attackers, assuming they are in the attacking war coalition. Units can move through the province without being added to the assault provided they remain in motion. Enemy units entering the province will trigger a battle, which puts the assault "on hold"; if the assaulting side wins the battle, then the assault will resume.
Once an assault is underway, the combat system is used to resolve what happens. Generally, there are sequences of fire and then shock in the combat, with each side inflicting loss of men and morale on the other. This happens repeatedly, until the assault ends (see below).
Die roll modifiers in assaults
The DRMs that apply in assaults are as follows:
- leader DRMs, same as for combat
- the fort's level is used as the defenders' DRM, unless there is a breach
- morale effects seem to exist, same as for combat
Inflicting force power
In assaults, only infantry and artillery can inflict damage for the attacking side. The firepower and shockpower of cavalry is zero. Infantry, cavalry, and artillery present in the attacking side take damage normally. On the defending side, there will never be cavalry, but all units in the garrison can inflict damage on attackers.
CRT column determination
The tables used to determine which CRT column to use in assault are given below. Note that unlike normal combat, the CRT determination for the defender is the same for both fire and shock.
tech 0-8 9-13 14-17 18-25 26-34 35-50 51-60 0-8 C C D E E E E 9-13 B C D E E E E 14-17 B B C D D E E 18-25 B B B D D D E 26-34 B B B C C D E 35-50 B B B C C D D 51-60 A A B B C C D
tech 0-8 9-13 14-17 18-25 26-34 35-50 51-60 0-8 B B C C D D D 9-13 B B C C C D D 14-17 A B B C C C D 18-25 A B B C C C D 26-34 A B B C C C C 35-50 A B B B C C C 51-60 A A B B B C C
tech 0-8 9-13 14-17 18-25 26-34 35-50 51-60 0-8 A B B B B B B 9-13 A A A A A B B 14-17 A A A A A A B 18-25 A A A A A A A 26-34 A A A A A A A 35-50 A A A A A A A 51-60 A A A A A A A
End of an assault
An assault typically ends with one of these outcomes:
- the attacking side loses all morale, and stops. The siege continues provided there are enough troops remaining.
- the defending side loses all morale. The city is captured.
- the defenders are killed to the last man; the city is captured.
Other ways that an assault can end are as follows:
- peace is declared while the fighting is ongoing
- one force is annexed by a third country
Unlike battles, assaults do not gain or lose warscore except that the successful capture of a city in any manner gives a +1% warscore in battles.