Advice on ground invasions

[Dalamar42 (OP)]

I am currently trying my hand at ground combat for the first time by attempting to dislodge some precursors from a planet with a deserted intact colony and as part of this I am trying to figure out what works best for ground units.   

Currently I am constrained on troop transport capacity so I can only transport and drop 4x 80k ton divisions at a time.  Given that combined arms warfare doesn't seem to have any effect in the game am I correct that it would be best for me to make fully armoured divisions (+ ART, AA, LOG) with no infantry for this invasion?

As best I can tell there are just three reason why I might want to opt for infantry:

• cost, which doesn't apply because I'm constrained on transport capacity, not GU training capacity
• terrain training, which also doesn't apply because the planet is a dessert so not much worry there
• fortification, which again doesn't apply because I'm the attacker

And one other question, if I land the army with no units set to front line attack, wait for it to fortify, then set some units to front line attack and the rest on front line defence, I assume the units set on defence will not participate in combat, correct? Otherwise this feels like it could be a way to cheese getting fortification bonus in offence (which I wouldn't do anyway for RP reasons, but I kind of want to understand how things work for now).     In this scenario I am assuming the defenders will not choose to attack me so they don't lose their fort bonus.   

[Droll]

Im spoilering my answer cuz this should probably be in the spoiler thread as it concerns spoiler races

For RP reasons you might like to bring AA but AI currently do not use CAS which means AA is basically AT with half pen. From since space is limited I would recommend heavy mechanised or full armour templates. Light vehicles have the highest evasion rating which can make them more durable than heavies against AT in the face of technological disadvantages. Heavies are useful because they will be able to shrug off all the spam from infantry CAP weapons that precursors have.

In fact the basic infantry unit of the precursors have CAP weapons which makes infantry a generally bad choice unless youve out teched the precursors with respect to power armour. Their presence also means that you need vehicles armed with CAP/HCAP (use HCAP if their armour is too strong, CAP otherwise) to spam them down. DO bring AT as well against their light vehicles

If you are specifically concerned about the terrain, desert is the only terrain which vehicles can actually have training for. It also reduces the max fortification of the defenders (only terrain to do so) so the terrain is actually an advantage for you (I always try to terraform planets to not be deserts for this reason).

As for defending in an assault defending troops can still contribute to the attack but only if the enemy has put their divisions on attack. I always have an infantry defensive line for RP as it makes sense for the infantry to follow behind the mechanised who are breaking through. However fortification takes time, and combat in a precursor outpost is short and brutish. Add to this that you are on a desert and from a gameplay perspective is not ideal.

Edit: I am a fool who doesn't know how to spoiler apparently

[Dalamar42 (OP)]

My question was not just about the precursors which I didn't make very clear, but this helps a lot.  Thanks!

Two follow ups based on that:

You mentioned using CAP instead of HCAP depending on target armour which makes sense.  Am I correct in assuming there is no downside to just defaulting to HCAP aside from cost? As in HCAP is not penalised in any other way compared to CAP.   

I've seen evasion referenced in a few other threads as well, but I don't understand how it works mechanically.  I couldn't find it in Steve's posts about C# ground combat and also I don't see it mentioned anywhere in the ground forces menu of the game.  Is there a written reference for this that I can go through?

PS: Good point about spoilers.  I edited my first post to hide the spoiler race name. 

[Droll]

My question was not just about the precursors which I didn't make very clear, but this helps a lot.  Thanks!

Two follow ups based on that:

You mentioned using CAP instead of HCAP depending on target armour which makes sense.  Am I correct in assuming there is no downside to just defaulting to HCAP aside from cost? As in HCAP is not penalised in any other way compared to CAP.   

I've seen evasion referenced in a few other threads as well, but I don't understand how it works mechanically.  I couldn't find it in Steve's posts about C# ground combat and also I don't see it mentioned anywhere in the ground forces menu of the game.  Is there a written reference for this that I can go through?

PS: Good point about spoilers.  I edited my first post to hide the spoiler race name.

You are constrained on space, IIRC HCAP is 20t while CAP is 12t, if your CAP can reliably penetrate enemy infantry HCAP is completely inferior cost and space wise as it does not do more damage or shots than CAP does.

I think you can see the evasion chance of units in the part of the UI where you select which base type your ground unit will use. I forget the specifics of how it works but I believe that the dodge stat of a unit modifies enemy hit chance along with everything else.

To give examples infantry have a dodge rating of 0.6 - attack hit probabilities on infantry are multiplied 0.6 effectively giving them a 40% dodge
Light vehicles have 0.4 which means they have 60% dodge
Super heavies have 0.95 so they only get 5% dodge
Statics have 1 which means that they do not have any innate evasion - incidentally they also cannot be part of breakthroughs in combat

It is an abstraction of how mobility, size and stealth can make certain units much harder to hit I don't actually remember where on the forums it is but if it is at all evasion would be in the ground section of the 1.00 changelog.

[Dalamar42 (OP)]

You are constrained on space, IIRC HCAP is 20t while CAP is 12t, if your CAP can reliably penetrate enemy infantry HCAP is completely inferior cost and space wise as it does not do more damage or shots than CAP does.   

Ah yes you're right.   I was fixated on cost and didn't see the size difference.   

I think you can see the evasion chance of units in the part of the UI where you select which base type your ground unit will use.    I forget the specifics of how it works but I believe that the dodge stat of a unit modifies enemy hit chance along with everything else.   

To give examples infantry have a dodge rating of 0.   6 - attack hit probabilities on infantry are multiplied 0.   6 effectively giving them a 40% dodge
Light vehicles have 0.   4 which means they have 60% dodge
Super heavies have 0.   95 so they only get 5% dodge
Statics have 1 which means that they do not have any innate evasion - incidentally they also cannot be part of breakthroughs in combat

It is an abstraction of how mobility, size and stealth can make certain units much harder to hit I don't actually remember where on the forums it is but if it is at all evasion would be in the ground section of the 1.   00 changelog.   

Ok I got it now.  The UI calls it `Hit Mod`.  Thanks

[Barkhorn]

I don't believe there is ever a reason to ever make medium or heavy bombardment vehicles.  These two unit types should always be either in support or rear echelon positions, and so do not meaningfully benefit from being vehicles.  You can get more guns per ton with static artillery as opposed to vehicle artillery.

[Droll]

I don't believe there is ever a reason to ever make medium or heavy bombardment vehicles.  These two unit types should always be either in support or rear echelon positions, and so do not meaningfully benefit from being vehicles.  You can get more guns per ton with static artillery as opposed to vehicle artillery.

Survivability, remember that medium vehicles and larger get more components which means more shots, but you forget that artillery vehicles have one chief advantage over statics - they benefit from evasion which means that enemy counter battery fire is less effective. Ultra and super heavies in particular can mount their respective armour levels which makes them very resilient to enemy fire (plus they have more components which means more shots per vehicle).

Having more guns does not necessarily translate to more overall artillery fire during an invasion - how long those guns last is in many cases as important as the initial quantity. You static guns will be more numerous at the start but will die at a faster rate than their vehicular counterparts, which could make them fire less overall.

I haven't done the monster math though so I don't know if my point would survive scrutiny but there is an argument for having vehicle artillery as opposed to static.

[xenoscepter]

I don't believe there is ever a reason to ever make medium or heavy bombardment vehicles.  These two unit types should always be either in support or rear echelon positions, and so do not meaningfully benefit from being vehicles.  You can get more guns per ton with static artillery as opposed to vehicle artillery.

Until they start getting shot at by counter-battery fire...

[Migi]

I've seen evasion referenced in a few other threads as well, but I don't understand how it works mechanically.  I couldn't find it in Steve's posts about C# ground combat and also I don't see it mentioned anywhere in the ground forces menu of the game.  Is there a written reference for this that I can go through?

If you are defending you get fortification bonus as your defence.
If you are attacking you get evasion stat as your defence.
Defence in both cases is a chance for your unit to avoid an enemy attack, doesn't affect armour or HP.
Because different types of units get different evasion, fortification and max armour types they are more useful in either situation.

As for what works best, it is difficult to say without knowing the exact enemy stats and composition, and then doing a bunch of math.
As a general rule static units are not useful in offensive situations.
If you are designing units for this specific assault, apply any relevant environment training that you have available (extreme temperature, pressure grav, high or low pressure etc).
There are always trade offs, IIRC you get most firepower per tonnage if you use infantry weapons but you are limited to light weapons and are very squishy.
IIRC light vehicles have the best evasion, however they are limited to light armour so they might be vulnerable to shots which medium vehicles could survive. IIRC they are slightly less tonnage efficient than other vehicles.
Medium vehicles can take medium armour but cost more, are larger and have lower evasion than light vehicles so they will get hit more often.
IIRC Heavy and super heavy vehicles have the same disadvantage and advantage vs lighter vehicles.

[Jorgen_CAB]

I have done both the tests and the maths... by far the cheapest artillery gun is the best given technology are equal. This has to do with cost and how more shots and more artillery pieces always trump heavier more armoured artillery pieces.

They reason for why you want to armour and put artillery on a vehicle is that they take less space for the same offensive and survivable capacity on a ship that can only bring a limited number of troops. If you need to fit a regiment with all logistical and support units into a 25000t transport ship you are better of to make the equipment as expensive and compact as possible.

But... if you have time on your side and can use the same ship to transport multiple troops from one place to the other then using cheap artillery is better from an efficiency perspective in terms of resources and time spent on producing them.

It obviously also take away all role-playing elements from that as well. You might perhaps view it from a humanitarian perspective and want your troops to have the best possible chance to survive even if it means more expensive units. It is a valid mindset. In real life survival-ability is also very important to preserve experience, in the game it might not be as important as in real life. The same can even be said for ships as well, it is not important enough to save ships and crew to preserve experienced crew, in reality in real wars this is a really key thing to do.

Any way... cheap artillery of the same tech level will always win against expensive armoured artillery.

Static artillery are hands down the best artillery for defensive fortification worlds. Armoured vehicles are  best for assaults as they give the best protection for the least size. The evasion stats is pretty much only usable for formation that is attacking. So any formation that is in defensive, support or rear echelon use their fortification level. Most assaulting armies will have little to no fortification.

The ground unit mechanic is basically made so cheap units are the most efficient in terms of actual combat strengths while expensive troops is best when it comes to space constraints. If this was not the case then you would build nothing but expensive max armoured troops, more or less.

[Droll]

I have done both the tests and the maths... by far the cheapest artillery gun is the best given technology are equal. This has to do with cost and how more shots and more artillery pieces always trump heavier more armoured artillery pieces.

They reason for why you want to armour and put artillery on a vehicle is that they take less space for the same offensive and survivable capacity on a ship that can only bring a limited number of troops. If you need to fit a regiment with all logistical and support units into a 25000t transport ship you are better of to make the equipment as expensive and compact as possible.

But... if you have time on your side and can use the same ship to transport multiple troops from one place to the other then using cheap artillery is better from an efficiency perspective in terms of resources and time spent on producing them.

It obviously also take away all role-playing elements from that as well. You might perhaps view it from a humanitarian perspective and want your troops to have the best possible chance to survive even if it means more expensive units. It is a valid mindset. In real life survival-ability is also very important to preserve experience, in the game it might not be as important as in real life. The same can even be said for ships as well, it is not important enough to save ships and crew to preserve experienced crew, in reality in real wars this is a really key thing to do.

Any way... cheap artillery of the same tech level will always win against expensive armoured artillery.

Static artillery are hands down the best artillery for defensive fortification worlds. Armoured vehicles are  best for assaults as they give the best protection for the least size. The evasion stats is pretty much only usable for formation that is attacking. So any formation that is in defensive, support or rear echelon use their fortification level. Most assaulting armies will have little to no fortification.

The ground unit mechanic is basically made so cheap units are the most efficient in terms of actual combat strengths while expensive troops is best when it comes to space constraints. If this was not the case then you would build nothing but expensive max armoured troops, more or less.

It does make sense, elite troops lead assaults while the regulars/militia defend/delay until the former can arrive to reinforce.

[ExChairman]

mmmhhmmm how do we resupply ground units

[Droll]

mmmhhmmm how do we resupply ground units

When designing units you have the option to give them logictics components, such units carry additional supply. From my experience, supply trickles down the OOB hierarchy, so logistics units at the top are used up first and then units will search closer and closer until they reach their own formation.

There is no benefit for having supply units inside a combat formation as supply gets used the same regardless of position in the OOB so make a large logistics division with nothing but supply trucks (marked as non-combat) and put them on the same system body as the guys you want to resupply.

Note that infantry supply can only supply its own formation whereas vehicular supply vehicles can supply anyone.

[liveware]

I don't believe there is ever a reason to ever make medium or heavy bombardment vehicles.  These two unit types should always be either in support or rear echelon positions, and so do not meaningfully benefit from being vehicles.  You can get more guns per ton with static artillery as opposed to vehicle artillery.

There is a slight weight advantage to fielding a medium vehicle with 2x bombardment weapons instead of 2x light vehicles with 1x bombardment weapon each.