[FEATURE REQUEST] Externalize the chance to spawn retaliation mission

[Meridian]

Hello devs, modders, all,

Since the time I first heard about XcomUtil, I have always played XCOM on Superhuman difficulty.
Most of my games were relatively similar... I shot only very few UFOs down (more Elerium, more loot, etc.) and the games lasted 6-10 months, not more.

Currently, I am playing FMP with following changes to everything I did before:
1. game lasts longer (14 months and counting)
2. I shoot down more UFOs for the viewers (~0% in early game, ~50% mid game... and now I reverted back to almost 0% late game, I'll explain why in just a moment)
3. most of alien missions have more UFOs than vanilla

My problem is, that I am completely overrun/spammed by Alien Retaliation.
I am shooting down only the "necessary minimum", and the game generated 14 retaliation missions already (cca 3 each month, in the last 5 month).

I don't mind an occasional base defense mission, but having to play 3 a month is just too much
(and I consider it the most boring mission of all... even more boring than TFTD bug hunt missions).

Warboy and Volutar have confirmed that the numbers are correct, i.e. as in the original.

... but since the original suffered from the difficulty bug, (I think) they have never balanced it.
The chance to trigger a retaliation grows in a linear fashion (4,8,12,16,20%) with the increasing difficulty... BUT the number of spawned retaliations grows much faster!!

I did some simplified calculations (lower estimates) and the results (attached) are really scary.

I am not asking to change the numbers in the vanilla... shorter gameplays and fewer shot down UFOs keep the number of retaliations somehow reasonable.
But, when playing mods, this has escalated and is now completely out of control.
I was forced to edit my save to escape the exponentially increasing number of retaliations.

----------------

So, what I am asking for is:

1. @players: do you have a similar experience... or am I just going crazy? also, can someone double check my calculations?
2. @developers: could you externalize the percentage for each difficulty, so that we can override it in the mods, which have longer gameplay than vanilla? Looking at the source code, it should be just a few lines of code... pretty please, with a sugar on top 

Cheers,
Meridian

PS: (if implemented) for FMP, I would recommend the following percentages: 4,7,9,11,12%

[Dioxine]

Yes - 1-2 simultaneous Retals going on every month is normal. However, the actual number of Base Defense missions can vary wildly, depending on base placement (and probably its crew size). While the number of Retals going on seems correct, last few playthroughs I got attacked maybe twice-thrice per year. However, this is about Piratez - the fact that the Retal ships are impossible to tackle early-game, means I try to ride out the retal waves in hopes they won't find me. You're probably shooting down the retal vessels, which, I imagine, may lead to exponential growth of the Retal missions... If it's indeed the case, I think it's quite silly - shooting down Retal ships shouldn't spawn more Retals.

[7Saturn]

Well, I experience a lot of retal-missions in late game, however, most of them are simply searching for the bases. Only a few actually find my bases. And as I once realized: It's absolutely not useful, to build defenses enough to hold them of from your base (e. g. four fusion ball defenses + 1 grav shield, leading to almost no chance to penetrate the base, however, leading also to annoyingly frequent attacks on the bases), once they found it. Better let them find you one day and kill them, than getting bugged once every three days. They will start from scratch with searching, instead of coming again and again. As a result, currently, I don't even bother to shoot down those scouting ufos, as that further increases the likelyhood of retal missions. Doing so, at least the number of actual base attacks is a little more reasonable. However, I rarely play on super human, as I play the game for fun, not for a challenge. There are enough challenges in real life, so I don't need any additional virtual ones. =) So I don't exactly know, how this progresses on super human, and I never played a complete mod, which might rely on that.

[Hobbes]

You can simply reduce the number of monthly retaliations by editing the MissionScript.

Besides the automatic retaliation roll that comes from shooting down UFOs the game also adds an extra retaliation mission starting about month 7 on superhuman. Remove this extra mission and you should get less retaliations.

[Meridian]

You can simply reduce the number of monthly retaliations by editing the MissionScript.

Besides the automatic retaliation roll that comes from shooting down UFOs the game also adds an extra retaliation mission starting about month 7 on superhuman. Remove this extra mission and you should get less retaliations.

It starts on month 10 on superhuman (column E in my calculation sheet).
But regardless, it makes only for a fraction of the retaliation missions, compared to the ones spawned by the shot down UFOs... that's what I was trying to illustrate.

Also, I have better numbers from my LP as a real world example:
- UFOs spawned (by Feb 2000): 183
- UFOs shot down: 51 (27%) -- notice this is much lower than the average players does (I think)
- Missions total: 50
- Retaliations total: 14 (28% of all missions!)
- Retaliations generated by mission script: 4
- Retaliations spawned: 10 (19.6% real rate... which nicely fits with 20% theoretical rate)

If I shot down let's say 50% of UFOs, I would have ~20 spawned retaliations compared to 4 generated by mission script so far.
Also they would make 24 of 60, i.e. 40% of all missions.
And if I started shooting them down from the beginning (instead of from July/August), it could easily be more than 50-60% of all missions...

EDIT: look at the summary for Beginner and Superhuman, when theoretically shooting down 100% of the UFOs... on Beginner you get 0.33 retaliations per other mission, on Superhuman 16... that's almost 50-times more on Superhuman than on Beginner (not 5-times as the rates 4% and 20% may suggest)

[hellrazor]

Ok i think this really needs some addressing.

So we do have additional random retaliation mission, which do increase with difficulty?
Ok i see the original developer probably never balanced this, as you mentioned before.

[Hobbes]

After some code digging and help from Warboy, here's the detection range of UFOs while searching for XCom bases on Retaliation missions:



Keep retaliation UFOs away from the circle and you'll prevent base defense.

[hellrazor]

After some code digging and help from Warboy, here's the detection range of UFOs while searching for XCom bases on Retaliation missions:



Keep retaliation UFOs away from the circle and you'll prevent base defense.

Hm.. does the circle size change if you have a mindshield buildin base, or does it only reduce the detection possibility in the circle?
EDIT: How did make is visible? Change radarrange of small radar:D?

[Hobbes]

Hm.. does the circle size change if you have a mindshield buildin base, or does it only reduce the detection possibility in the circle?
EDIT: How did make is visible? Change radarrange of small radar:D?

From what I've understood it works exactly like a radar: a UFO can only detect bases upon its radius and for each certain amount of time spent inside the radius it has a % chance of detecting a base. Mind Shield reduces the chance of the UFO detecting your base. 

[Arthanor]

That's an interesting twist! Shooting down UFOs on retaliation missions which leads to more retaliations for exponential growth of retaliations is something I had never thought of. But that just makes the solution obvious: Don't shoot down UFOs on retaliation missions (unless you are pretty sure they are going to get inside your base's circle).

I fully agree with externalizing the retaliation chance (and pretty much every other parameter, probably). However, I think this adds a much needed pressure on the player on the strategic level. The tactical level of XCom is challenging, but it is a rather difficult game to actually lose except from early disastrous terror+base attack.

Retaliation UFOs also spawning retaliations makes sense: They are looking for you, you hurt them. Now they devote even more resources to finding you since they know you must be around there and that you are dangerous.

[Warboy1982]

aaaaaaaactually shooting down a retaliation UFO probably won't trigger a new retaliation mission, there can be only one retaliation in a given region at any given point in time, so assuming the interceptor came from the base being targeted, no new retaliation could occur. if it came from a different base, of course, that alters things.

[Meridian]

Hmm, I didn't consider that in my calculations... also not sure how to do it... but it should lower the numbers down, maybe even significantly... I think I will just have to make a real test run...

[Hobbes]

Hmm, I didn't consider that in my calculations... also not sure how to do it... but it should lower the numbers down, maybe even significantly... I think I will just have to make a real test run...

Yeah, I think your calculations are valid but for a specific scenario, based on your game play. If you regularly use certain tactics like intercepting UFOs before they reach their target region, or sending craft to patrol and shoot down UFOs in regions where you don't have a base and alien activity is being reported on Graphs, then you'll able to deflect some of those retaliation missions away from your bases. How much I don't know but I usually don't get so many base defense missions as you did.

[Dioxine]

assuming the interceptor came from the base being targeted, no new retaliation could occur. if it came from a different base, of course, that alters things.

A tidbit of info - AFAIK this is no longer true when you're using craft for detection; from my observations, it seems the retaliation (the kind spawned by shooting down an UFO, not Retal Monthly) is conducted over a region where the shooting took place, even if you have no base in that region. The origin of the interceptor seems irrelevant in such a case.

[Hobbes]

The origin of the interceptor seems irrelevant in such a case.

The origin of the interceptor is important. This is the code that generates retaliation missions after a UFO shootdown:

Code: [Select]

std::string targetRegion;
if (RNG::percent(50 - 6 * _game->getSavedGame()->getDifficultyCoefficient()))
{
https:// Attack on UFO's mission region
targetRegion = _ufo->getMission()->getRegion();
}
else
{
https:// Try to find and attack the originating base.
targetRegion = _game->getSavedGame()->locateRegion(*_craft->getBase())->getRules()->getType();
https:// TODO: If the base is removed, the mission is canceled.
Basically, first the game rolls for a retaliation where the shootdown took place, and the higher the difficulty, the lesser the chance of a successful roll (50% on easy, 26% on superhuman). If this fails, then the game looks for the base where the interceptor originated and generates the retaliation mission on that region.