Zombie Attack

[Vangrimar1]

Is it possible to make the attack of krissalid not turn into zombies with one blow, but depend on armor. If the armor is not broken, then there is no turning into a zombie. I would like to add virus infected zombies that infect others when bitten. But they should be dangerous only to unprotected soldiers.

[Bobit]

You can have a chance for zombificaiton via specialChance and make units immune to zombification via zombiImmune, ctrl-f through the reference at https://www.ufopaedia.org/index.php/Ruleset_Reference_Nightly_(OpenXcom).

I agree that basing zombChance off of hp/dmg/armor is better.

[Vangrimar1]

Thanks. While there are no other options, it will do.

[Thermite]

Thanks. While there are no other options, it will do.

Somewhere here, there is a mod that does just that (revamp chryssalids), it's somewhat recent even. If I find it I will link it here.

Edit:

This mod has two main tweaks and several lesser ones.

Main changes:
(If someone thinks these changes nerf Chryssalids, read through the lesser changes. They are still somewhat nerfed, but lesser changes also give them upsides they didn't have).

1. Originally, Chryssalid's zombifying attack succeeds even if it inflicts no damage. Yes, it fails if they miss completely (i.e. melee accuracy check is failed), but if they hit, then the victim is zombified even when all damage is negated by armor. It makes no sense to me: how are they supposed to inject their venom and plant an egg if their ovipositor (or whatever) didn't pierce the armor? Actually, on this forum there was a suggestion even to make their zombification work only after the damage they inflicted has killed the victim, but I prefer to think that even if they made just a scratch of 1 HP, it's enough to inject the venom. Let's suppose it's potent enough to kill the victim instantly. Still, if there is no scratch => no venom is injected or egg planted => no zombification. So the first change is that the attack should reduce the victim's health by at least 1 HP for zombification to happen.

2. Originally, Chryssalids hatch instantly. If you kill a zombie in the exact same turn in which it was zombified, a Chryssalid is gonna spawn from its remains. This also makes no sense to me. Even though the UFOpaedia mentions Chryssalid's high metabolism, there is a difference between high metabolism and developing a human-size organism from a small egg (Chryssalids carry about twenty of them, according to the same entry in UFOpaedia) in a second. It would be okay in a fantasy setting ("it's magic", and that's it), but not in a sci-fi setting. If they had metabolism rate that fast, they would have to have 100% health recovery, so that if they were not killed in one turn, they would restore from 1 HP to full health by the next turn. And also they would have to be only about 20% vulnerable to all types of damage to reflect the fact that they regenerate almost more quickly than you can harm them.

Also, from the gameplay point of view, it makes the player postpone dealing with zombies: since the zombie is already created, the situation is not gonna get much worse if you leave it alone, but it will get much worse if you kill it and thus hatch a Chryssalid. I think, if the Chryssalids had a reasonable delay before being able to hatch, it would be better by putting the pressure on the player to deal with zombies as soon as possible.

Hence the second change: Chryssalid hatching has a delay of zombification turn (ZT) + 1 turn. During that delay they are spawned dead (unfortunately, making them not spawn at all is impossible). If a zombie is killed on ZT + 2, the Chryssalid is spawned severely underdeveloped, i.e. having 1/3 of its max health and 1/3 of its most important stats (TUs, stamina, reaction, strength, and melee). If the zombie is killed on ZT + 3, the Chryssalid is spawned somewhat underdeveloped, i.e. having 2/3 of its max health and 2/3 of its most important stats. Only on ZT + 4 and later they are spawned fully developed.

Lesser changes:

1. Originally, if a zombie is not killed, the Chryssalid never hatches on its own. Now they shed the husk of the zombie on the ZT + 6.

2. Originally, a Chryssalid keeps attacking its victim until the latter is considered dead, i.e. has 0 or less HP. It tries to "actually kill" the victim even if one of its attacks has already landed, despite the fact that one successful attack is all that's needed and it's not necessary to actually kill the victim. But now, as soon as the Chryssalid lands the first successful strike (deals at least 1 damage to health), it stops attacking the victim and goes on to the next.

3. Now Chryssalids (and zombies too) have no sense of self-preservation. Burning fire? Not enough TUs? Pfft! They don't care, they just charge in. Don't go thinking that makes them less of a threat: it actually makes them far more menacing than before, especially considering the previous change (even if they stop 2 tiles from you, becoming sitting ducks, it still feels more threatening).

4. Especially also considering that they now have a melee skill of 150. Basically, they will never miss, unless they are severely wounded (or underdeveloped). Your hope is the thickness of your armor (and killing them before they get to you, of course).

5. Zombies have somewhat less damaging attack but somewhat more HP than before.

6. If you have the option "Alien bleeding" enabled, zombies previously would receive fatal wounds, same as all other 1-tile units. Now zombies are immune to wounds. They are also immune to stun.

7. All "excessive" damage from the hit that kills a zombie (i.e. the amount of HP that the zombie has in the negative after the hit) is inflicted on the hatching Chryssalid that was inside of it. This damage is still decreased by the Chryssalid's armor, of course. But underdeveloped Chryssalids have significantly worse armor (only for this carryover damage. After they spawn, they have the regular Chryssalid armor). Unfortunately, they get no fatal wounds from this carryover damage, even with the "Alien bleeding" enabled.

8. Speaking of the Chryssalid armor, UFOpaedia says it's "surprisingly vulnerable to explosive ammunition". Now it actually is. (Originally, it wasn't). To compensate for it, I somewhat increased its resistance to armor piercing and melee (it wasn't resistant to them at all) and greatly, to stun.

9. Some people prefer killing civilians "just in case" when there are Chryssalids around. Sorry, but this won't do X-COM should protect the population. I doubled the value of civilians (including the Armed Civilians mod): now you get 60 points for each rescued civilian, lose 60 for each one killed by aliens, and lose 100 for each one killed by X-COM.

Have fun!

---

Acknowledgements

Thanks to Meridian for OXCE with its huge possibilities for modding and to Yankes for his scripting language and consultations on how to use it.

---

Two important warnings:

1. At the moment of creating this post you have to be using the latest nightly version of OXCE for this mod to work, otherwise the Chryssalids spawned at the start of combat are gonna spawn dead.

2. Currently, the Chryssalids that are supposed to spawn dead due to the introduced hatching delay, are gonna be spawned kinda "undead", i.e. with 0 HP, but in a "live" state. This is not that big a deal: they can't take any action and gonna die as soon as the turn in which they were spawned ends, or as soon as they are shot at (even if the shot misses), whichever comes first. Besides, this is gonna change soon, in one of the coming nightly versions of OXCE.

[Vangrimar1]

Yes, I downloaded this mod earlier, but I don’t understand scripts well and can’t isolate the part that is responsible for zombies. I would be grateful for the help.