Pitch ditches can be lit by other (even hostile) AI players

[Heroesflorian]

As I just mentioned there: https://github.com/Sh0wdown/UnofficialCrusaderPatch/issues/191#issuecomment-451573777

AI players can generally light pitch ditches on fire (intentionally) with flaming arrows, even if the pitch ditch was made by other players, no matter whether dead or still alive, allied or hostile. This is especially annoying when defensive archers of several AI characters of different factions are in shooting range of each other's outer pitch ditches, as then the utility of them is often not just nullified but even reversed.

[PitchNeeded]

It can be good if AIs can light their dead allies' pitch ditch though. This feature should be kept I think. Makes some unexpected fire that can make it harder for the human player to siege an enemy!

That happened when I was playing a match where I killed Wolf who was right next to Wazir and then prepared a force to attack Wazir. My troops were passing over the old ruin of Wolf's castle on their way to attack Wazir's castle when Wazir managed to light pitch way outside where his usual pitch was, so it must have been Wolf's old pitch ditch that was lit.

[Monsterfisch]

ais tend to send their troops into fires themselves anyways I think the bigger underlying problem is maps where the keeps are placed too close to one another so pitch trenches overlap with the ally castles. (at least when it comes to allied ai) as for hostile as I have not seen hostile tower archer lit enemy trenches on fire unless by accident with a fire Balista. but i could just not have noticed it actively.

[Heroesflorian]

It can be good if AIs can light their dead allies' pitch ditch though. This feature should be kept I think. Makes some unexpected fire that can make it harder for the human player to siege an enemy!

I do not think that is a convincing argument though. Dead allies' pitch can be lit once - for a nice surprise, sure - but alive allies' pitch can be lit on fire "endlessly", which often causes allies' buildings and troops to burn down - and just recently we saw some Udwin AI battle videos where Caliph lit on fire Emir's entire castle that way several times.

maps where the keeps are placed too close to one another so pitch trenches overlap with the ally castles.

Yep, but with map size being an unchangeable constant for now, this affects most maps to some extent (depending on what castles are used, ofc). Even maps with relatively well-spaced keep positions - e.g. "Green Haven" - have castles quite close to one another.

And even more annoyingly, AI can also light hostile pitch ditches, which really makes no sense.

Now, regarding the lighting of hostile pitch ditches... I just setup two quick test aivs for demonstration purposes:

• A Saladin (here in orange and allied with the human player) with a massive frontal pitch ditch, and with no fire ballistae, no braziers and no fire throwers in range of the pitch ditch.
• An Emir (here in yellow and hostile to the human player) with no pitch but braziers and archers atop his towers.

As soon as any soldiers of Saladin (an archer in this case) entered the pitch ditch and shooting range of Emir's archers next to braziers, they light on fire Saladin's pitch ditch to kill Saladin's archer:

Shortly after, Saladin rebuilt his massive pitch ditch and Emir lit it again when some swordsmen of Saladin marched across it.

And for those still in doubt, this is 100% reproducible, independent of the size of the pitch ditch, even 1-tile ditches get lit precisely and on purpose by (hostile) AIs, but with a larger one it is easier to show it.

To make things even worse:

• Fires lit by a player cannot directly spread to own buildings of the same player. This means if a player (let's call him "A") lights his own pitch ditch for defense, the fire will not spread to any adjacent farms or other buildings of player A.
• But fires lit by another player player (let's call him "B") CAN directly spread to buildings on player A. This means if player B lights the pitch ditch of player A, and the pitch ditch was nearby any castle buildings, farms, quarries or anything else, those buildings will be set on fire as well, potentially causing a lot of economical and military damage to A - in addition to already losing both his pitch ditches and his own troops in the fire.

Considering human players do not see hostile pitch ditches, I would say AI players shouldn't "see" or know about hostile pitch ditches either, and definitely should not be able to abuse them.

[Sh0wdown]

Is the AI actually shooting the pitches they don't own on purpose or was it just stray arrows hitting a pitch?

[Monsterfisch]

even 1-tile ditches get lit precisely and on purpose by (hostile) AIs

[Heroesflorian]

@Sh0wdown the AI shoots hostile pitch ditches on purpose, definitely, with same precision, priority and "reproducability" as their'd light own pitch ditches.

Also, regarding stray arrows... ...those may hit a pitch ditch, but won't light it on fire.

[Sh0wdown]

...those may hit a pitch ditch, but won't light it on fire.

Huh, I always thought that was possible. Interesting.

[Heroesflorian]

Huh, I always thought that was possible. Interesting.

Well, it works for fire throwers, and for fire ballistae "accidentally" setting on fire a building adjacent to the pitch ditch, and possibly it worked in SH1 for stray fire arrows as well?

Might be one of those "urban legends" that stick around for long... similar to the pikemen's ability to climb ladders, as shown on the intro loading screen, but not actually possible in Crusader.

Nonetheless, just to make sure, I did another round of testing, this time with a siege tower, driving it across the pitch ditch. As you can see, a lot of arrows aimed too far ahead as I kept changing directions, and did miss the siege tower and hit the pitch ditch instead. The pitch ditch did not catch fire, though. Obviously, stray arrows do not work to light pitch ditches "accidentally" for the AI either.

Also, I wondered why the pitch wasn't just lit intentionally to burn my siege tower up. Thus, shortly after, I tested again with some horse archers of mine instead of the siege tower - for a same result: No accidental lighting, nor intentional lighting, although certainly a bunch of (fire) arrows hit my horse archers, and also a bunch of fire arrows missed them and hit the pitch ditch. But then, some swordsmen of Saladin (i.e. the pitch owner) stepped onto the pitch ditch, and immediately, Emir set the ditch on fire once more... not sure why that distinction was made there, though... I certainly have already been victim of leftover pitch ditch from dead AI players that was then lit by another AI player with only my own troops nearby on a number of occasions over the years, so it cannot be a flat-out distinction between human and AI player troops...

Also, as an L-shape of 3 tiles of pitch ditch "survived" the big burning, I again sent my horse archers right onto it, which were impaled by many arrows but not burnt up. Then, a group of Saladin swordsmen and horse archers passed by (even 1-2 tiles next to the pitch ditch and not directly across the ditch, but still within burn radius), and Emir lit the little 3-tile pitch immediately...

Edit: Another test with an (allied) Philipp behind Saladin resulted in Saladin pitch ditches being lighted by Emir archers to burn Philipp troops. And right after that, Emir's special message triggered "Time flies when you are having fun! It has certainly flown well today!", with him grinning broadly. Who would have thought Emir to be such a cheerful fire devil! :D

That leaves me with the conclusion that definitely "abusing hostile pitch ditches" is not limited to the troops of the ditch's owner, but still leaves open why Emir ignored my troops regarding pitch lighting, when clearly the AI can employ other (dead) AIs' ditches against the troops of human players.

Edit: And, just for the sake of completeness, workers generally do not trigger pitch ditch lighting, ofc.

[gynt]

This issue has just been reported again by a user #944

What is the consensus on this? Fix according to this suggestion?

AI players shouldn't "see" or know about hostile pitch ditches just like human players, and definitely should not be able to abuse them.

[GRhin]

From a realism perspective, being able to burn them makes sense, so those going for realism should support leaving it as is. From a balance perspective, having pitch ditches being placed in range of your walls seems a bit unfair, they can't get troops there yet they can booby trap it, kinda frustrating that part of your map control is nullified, therefore I personally support leaving it as is, as it only really is usable when the pitch ditches are in range of your walls. Anything outside of that range must be lit by a fire ballista or fire throwers, the latter ofneeds to be in range of the pitch owners walls to be able to do so.