This document describes combat as implemented in PHost.
There are two types of combat in VGA Planets:
Regular combat happens when two units meet in space
after movement. Regular combat
can happen between two ships, or between a ship and a planet.
Units will fire their weapons (beams, torpedoes and
fighters) against each other and attempt to destroy or capture the
enemy. The largest part of this document describes regular combat.
Ground combat happens when a ship beams down colonists
to an enemy planet. Colonists will fight each other, until one
party survives. That party will keep the planet. Ground combat is
described in the last section of this
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After movement is complete, ships which end up on the same
position in space can engage in combat. Likewise, ships can attack
planets (and their starbases) and vice versa.
The standard combat system in VGA Planets can resolve battles
only using pairs of two units (i.e. two ships, or a ship and a
planet): if you have multiple ships attacking a common enemy,
they'll all fight that enemy one after the other. Your most
important tactical utility is battle order, i.e. the order
in which your ships fight. You can set that order using friendly
codes. PHost implements a similar battle order system as HOST 3.20.
There are a number of fleet combat
systems which resolve combat in a completely different way: all
ships at once. Those are not part of PHost, and are not described
here. There also are a few alternative 1:1 combat systems
which basically behave similarily to PHost.
Here are some basic rules concerning who will fight. More
details are below in the phase descriptions:
- Units must be at the very same position (same X,Y) on the map
to be able to fight.
- Fuel-less ships cannot attack.
- Fuel-less ships cannot be attacked (except by planets with
friendly code NUK).
- You will attack all enemy ships when you have mission
Kill. You can choose to attack only one
race by selecting them as Primary Enemy (and not using
the kill mission); recent PHosts allow you to combine that with a
permanent global enemy setting. If you
have neither the Kill mission, nor a
Primary enemy, you will not attack anyone. You'll still defend
yourself when attacked. You cannot attack players whom you have
offered a combat level alliance.
- Cloaked ships cannot be attacked.
- Cloaked ships can attack other ships if so configured
(AllowCloakedShipsAttack), but cloaked ships cannot
- Objects with matching friendly
codes do not attack. Remember that special friendly codes
(v4.0k:) Units will not attack each other if they
have no offensive potential against their opponent. This rule
applies in two cases: (a) Two freighters will never attack each
other, nor will ships without ammunition and beams. (b) A ship
will not attack an unarmed planet if it has only death rays.
Death rays are ineffective against
- If a planet takes part in combat, and that planet has a
starbase, those will combine their power and fight as one unit.
It is not possible to attack (or defend with) just the planet or
just the starbase.
Once PHost has determined what units will fight at a particular
place, it will sort the list according to battle order
values. You can choose battle order values for your units by
using (numeric) friendly codes.
- If your friendly code consists of only digits, that's the
battle order value. This can be used to enter values between 000
- The friendly code can also start with a minus sign, yielding
values between -99 and -00.
- A planet with ATT or
NUK will have a battle order value of
- Planets with other non-numeric friendly codes have a value of
1001 if they have defense posts, 1003 if they have none.
(v4.1e:) Ships with non-numeric friendly codes have
a value of 1000 if they have weapons and are aggressive by
having mission Kill or a primary enemy,
1002 if they have weapons and are not aggressive, or 1004 if
they don't have any weapons at all. Note that PHost
versions betfore 4.1e/3.5e did not distinguish between aggressive
and non-aggressive ships, they were giving all armed ships order
1000 and all freighters order 1002.
When two units have the same battle order value, the one with
the lower Id number fights first. When a ship and a planet with
the same Id number and the same battle order value fight, the ship
||(rule 5, this is a lower-case
letter "o" not the digit "zero")
||(rule 1, since PHost 4.0h; earlier
PHost versions handle only friendly codes consisting of exactly
three characters and would use rule 5 here)
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Combat consists of two major phases: Intercept Attack
("XA"), and the Aggressor/Opponent Phase, also known as
The intercept attack phase is only run when enabled in the
configuration (AllowInterceptAttack). During intercept
attack, ships which reach their intercept target attack their
target. A ship must fulfill all of the following conditions to be
considered for intercept attack:
- The ship must have a valid Intercept
- The ship must have a cloaking
device. Only cloak-capable ships can do Intercept
Attack. The ship will not - and in fact, can not - cloak during
the intercept (the common habit of calling this function
"cloak intercept" is therefore highly misleading).
- The ship must have fuel. Ships without fuel cannot attack.
- The ship must have a primary enemy setting which matches the
intercept target, either directly or via the
- The ship must not have offered a
combat level alliance to the target.
Friendly codes must not match.
The intercept target must satisfy these conditions so you can
- The target must have fuel. Ships without fuel cannot be
- The target must not be cloaked. Cloaked ships cannot be
Interceptors are processed in the correct Order of Battle. When
two ships intercept the same target, the one with the lower
battle order value attacks first.
(v3.4b:) In PHost 3.4a and below, as well as in HOST,
intercept attack does not honor battle order. Instead, ships fight
in order of decreasing interceptor Id.
Remember that Intercept Attack is only available for
cloak-capable ships. Most ships cannot do
Most combat happens in the Aggressor/Opponent phase. During this
phase, the following happens:
- Find an aggressor. This will use
battle order values. We start with the
ship with the lowest possible battle order value and work our way
up. Each aggressor fights all its possible opponents; after that it
can no longer be aggressor for this turn (but it still can be
- A ship must have the Kill mission
or a Primary Enemy to become an aggressor. It must have fuel.
- A planet must have the ATT or
NUK friendly code to become an
- Find an opponent for this aggressor. This will again
check all ships (and the planet, if any) in
- The aggressor cannot fight units whom he has offered a
combat level alliance. Likewise, two
combatants will not fight when they have
matching friendly codes.
- If the aggressor has no Kill mission, the opponent must
be of the race indicated by the aggressor's Primary Enemy.
- Planets cannot attack Klingons and Rebels
PlanetsAttackRebels), and they cannot attack
Assault ships (i.e., the Super
Star Destroyer; AllowImperialAssault).
- Fuel-less ships can only be attacked by planets using the
NUK friendly code. Fuel-less Bird Men
ships with weapons cannot even be attacked by these planets.
- A cloaked ship cannot attack planets.
- You cannot attack cloaked ships, except when
they have set their primary enemy to your race.
- Perform the battle between aggressor and opponent. Note that
PHost will assign sides on the VCR randomly, so you can't tell
from the battle alone who was the aggressor. This is unlike HOST
where the aggressor will always be on the right side.
- If the aggressor survives, try to find another opponent
(return to step 2).
- If the aggressor got killed or captured, or when all opponents
have been exhausted, find another aggressor (return to step 1).
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Battles are divided into battle ticks (sometimes
rendered as seconds). During each tick, a certain series of
events happens. The fight ends when a winner can be declared.
Therefore, a battle tick is to a fight what a turn is to a
Ships start at a distance of 58000 meters.
- Weapons recharge. See BeamRechargeRate etc.
- If a ship has fighters, and has not yet exceeded the
MaxFightersLaunched limit, it launches a new fighter.
- Fighters that are close enough to their enemy will fire.
Fighters that run out of ammo (StrikesPerFighter) will
- If the ships are close enough (TorpFiringRange),
torpedoes are launched. Torpedo tubes need time to recharge before
they can fire again.
- Likewise, if ships are close enough, beams are fired at enemy
fighters (BeamHitFighterRange) or the enemy ship
(BeamFiringRange). Beams need time to recharge before
they can fire again. The more they are charged, the more damage
the beams do.
- Fighters that come close try to shoot each other down
- Fighters move towards their enemy, or back to their base
- Ships move towards each other until StandoffDistance
Planets behave mostly identical to ships. They obviously cannot
move in the last step, but are otherwise treated the very same way
The battle ends immediately if one of the following happens:
- A unit exceeds the maximum damage (100% for most races, 150%
- A ship loses all crew.
- Both units run out of ammunition.
New v4.1a: When a fight does not progress, PHost will
cancel it. This does generally not happen in regular games, but
can happen when the combat configuration
has suboptimal values. PHost will cancel a fight if
StandoffDistance has been reached, but no unit has
taken damage, fired torpedoes, or lost fighters for 5000 battle
ticks. In this case, the fight ends as if both units ran out of
Combat is not deterministic. Weapon recharge is a probabilistic
process, and weapons have a certain hit/miss ratio. Therefore,
many fights have no predetermined outcome. Whereas HOST has just
110 possible outcomes, PHost has a theoretical set of 65536
If a ship ends the fight with 100% damage or more, it is
destroyed, and the opponent is declared winner of the
fight. This also applies to Lizard ships: although they can
fight until they reach 150% damage, they cannot survive any
further with more than 100% damage.
If a ship ends the fight without crew, the enemy can
capture it. He will man the ship with an emergency crew
of up to 10 crewmen (for simplicity, the capturing unit doesn't
lose crew by doing that). The ship will become passive for further
fights this turn. Unlike in HOST, planets can capture ships
If a ship has lost shields, crew or ammunition, or got damaged
in fight, it will carry over this damage to further fights this
turn. Shields will be recharged for the next turn, but damage
remains until you repair it. The first chance for repair is given
after combat: ships can repair themselves using supplies (see
If a planet ends the fight with 100% damage or more, it is
captured. The fight will have destroyed all its offensive
potential, so all the defense posts and the starbase will be
destroyed. At the default configuration, all colonists will have
been killed (see ColonistCombatSurvivalRate), and the
planet will be manned with a single colonist.
Damage is handled a little different for planets compared to
ships: whereas a 30% damaged Annihilation Class Cube with Mark 8
Tubes is still an Annihilation Class Cube with Mark 8 Tubes, the
planet (and its starbase) will lose some of the defense posts
making up its strength: if a planet with 50 defense posts gets 30%
damaged, it will lose 30% of its defense, and begin the next turn
with 35 defense posts. It will therefore start the next turn as an
undamaged planet that happens to be weaker than the turn
before. Put in other words: whereas ships keep their strength but
accumulate damage, planets simply lose strength, but don't get
If a planet/base combo fires ammunition, it will first take the
ammunition from starbase storage. The base will also receive
damage and lose tech levels if too badly damaged.
Combat results for ships,
Combat results for planets.
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Ground combat happens at the beginning of the turn, before
movement, in the CargoDump stage
of host processing. Ground combat happens whenever a ship unloads
colonists onto a hostile planet.
Preconditions for Ground Combat:
- The ship must be in orbit of a hostile planet. If the planet is
friendly, the unloaded colonists
will become part of the existing colony. If the planet is unowned,
it will be colonized peacefully.
- The ship must have fuel. Fuelless ships cannot use their cargo
- The ship may have any mission,
In ground combat, attacking colonists will fight the planet's
inhabitants. Depending on their strength, one party will survive.
Whereas attackers have only their GroundKillFactor,
defenders have GroundDefenseFactor as well as a bonus
from their defense posts. See
Ground Combat formulas for
details. If all parameters are known, ground combat is 100%
Effects of Ground Combat:
- Ground combat does not destroy planetary infrastructure. All
defense posts and the starbase will remain intact.
- If the planet (and thus, the starbase) changes ownership, the
base's build order will be canceled, hulls in storage will be
recycled, and the base's fix/recycle order will be cleared.
- If the planet changes ownership, all its
experience will be lost.
- Other planetary properties, such as tax rates, happiness, and
friendly code, do not change.
Imperial Assault is a special
case of ground combat.
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Last updated 31 May 2015.