Assault Gun & Tank Destroyer

[BlueTemplar]

A topic to discuss these two very special tank models.

I had hijacked another topic before (sorry) :
https://www.matrixgames.com/forums/tm.asp?m=4977385

ORIGINAL: BlueTemplar
No, both Assault Guns and Tank Destroyers are two times worse at Hard Attack than Medium and Heavy Tanks, and cost the same Metal but half the IP, unless this calculator is wrong ?
https://www.matrixgames.com/forums/tm.asp?m=4959387
[...]

Well, it was wrong !

ORIGINAL: GuardsmanGary
This sheet is missing calculations regarding tank destroyers. As you can see in the attached image I've input all the values from Shadow Empire into the design calculator but the soft attack/defense and hard attack/defense are not consistent. This is because the tank destroyer model type has an inherent 50% bonus to hard attack/defense and 50% penalty to soft attack/defense. This effect is most visible if you equip a tank destroyer with a howitzer. If you consult the design log you will you see a "modified for weapon type" entry after the initial attack score calculations are done that shows soft attack and defense being cut in half. This is very odd considering howitzers do not have a soft attack penalty. You'll see a similar entry for hard attack/defense that presents a value that is only 75% of the hard attack/defense value derived from firepower when for howitzers it should be 50%.

So, to recapitulate :

Assault Gun :
Medium Tank formation model (extra +10% AP movement cost penalty ; -60% Soft HP penalty, before Side Skirts).
Compared to Medium Tank :
-50% Hard Offensive Attack
-50% IP cost
Also, unlike Medium Tank, Assault Guns cannot mount 200mm plating, which might or might not be a bug ?

Tank Destroyer :
Heavy Tank formation model (extra +20% AP movement cost penalty ; -70% Soft HP penalty, before Side Skirts).
Compared to Heavy Tank :
-50% Soft Offensive & Defensive Attacks
-25% Hard Offensive Attack
+50% Hard Defensive Attack
(Hopefully these also apply the same way for the anti-hard weapons as for howitzers ?)
-50% IP cost

Of course, when deciding of the role and equipment for a tank, many other considerations can come up : see the first of the linked discussions. I'll probably add comments of my own about these here when I get to it.

[Sieppo]

Thanks for this. Have been trying to figure out the differences and benefits. I have actually a assault gun design in my current game that has better hard attack than my medium tank one (high velocity gun) and is half the IP price, which is nice.

[BlueTemplar]

Yeah, even with the same equipment, and all models up to date on latest tech, model performance can vary wildly with the 3 "final" design roll stats !

[zgrssd]

For all Models, Attack values are based on firepower and modified by both the weapon and model.

Weapon:
Howitzer has -50% on both hard values, or a division by 2
High Velocity gun has -75% on both Soft Values, or a divsion by 4

Additionally these modifiers should apply:
Tanks are offensive weapons
Any vehicles (track/wheel) with Guns get their Hard Defence value diminished by one third
No turret, less offensive potential
Any Tank without a Turret (The Assault Gun) has its Hard Attack Value divided by two.

Could you maybe verify - based on the Firepower and the actuall values - wich penalties or divisor apply to each value? That might help us get an idea of uses.

[BlueTemplar]

Well, the first 3 of the ones that you cite apply equally to *both* the "base tank model" and the "half-IP version", so they are of not much value for *comparing* them (at least for similarly equipped versions).

(They of course would be of interest if we were, for instance, comparing HVG tanks to howitzer artilleries...)

Thank you for reminding of the first two in case we need to compare Howitzers to HVGs on the tanks themselves.
(Though at this point you might be better off just using the calculator... once it's fixed !)
Oh, also we must not forget about Cluster Bombs adding +50% (?) to soft offensive & defensive attacks !

And the uses should be clearer now that only the differences -
(though I couldn't resist putting in the HP ratios and especially extra movement cost penalties for each "formation tier")
- are highlighted (and *all* the differences are !) between the "base version" and the "half-IP version".

[zgrssd]

Well, the first 3 of the ones that you cite apply equally to *both* the "base tank model" and the "half-IP version", so they are of not much value for *comparing* them (at least for similarly equipped versions).

I prefer just having the raw attack values and firepower for each unit. That way we can figure out if the Tank Modifier is replaced by the Assault Gun/Tank modifier. Or if it replaces it.

[GuardsmanGary]

Assault guns:
-50% hard attack for being turretless
-33% hard defense for tank defense penalty
-50% soft defense for infantry vulnerability

Tank Destroyers:
-50% soft attack and soft defense for being a tank destroyer
+50% hard attack and defense for being a tank destroyer
-50% hard attack for being turretless
-33% hard defense for tank defense penalty
-50% soft defense for infantry vulnerability
The stacking penalties and bonuses means that tank destroyers ultimately have:
-25% hard attack
+33.4% hard defense
-75% soft defense

All in all this means assault guns are strictly worse for hard attack than medium tanks but are otherwise equal in all other aspects relating to combat performance, and tank destroyers are strictly worse for hard attack but better for hard defense than heavy tanks.

Here's the all the relevant design log entries and model info for a tank destroyer: