The PC doesn't know there's something in that square without +SeeI. It doesn't make sense to me to ask for confirmation before attacking something you can't see and don't know exists, just like it doesn't if you accidentally bash a neutral/companion in a dark room.

Just equip the AMW or RotMC (if you got it) before entering Terinyo :) No one there should be hostile beforehand, and changing body armor in the wilderness was a free action, if I remember correctly.

If the PC doesn't see that invisible creature, they don't know if it's something they should attack or not. Logically then, they would have to either always be prompted or never (which is what currently happens). If the former, that could grow seriously annoying when the PC fights actually hostile invisible creatures, like Nuurag-Vaarn.

I think the current situation is already more than alright - with the exception of the one invisible NPC, Khelavaster. My proposal would be to just make Khelavaster visible by default, and add a line in the description that for some strange reason noone else in the village seems to react to his presence.

I don't feel that automatically attacking something that the player cannot see makes sense - in order to engage something in combat, doesn't one first have to know that there is something there to fight? I certainly cannot reconcile in my mind the image of an adventurer flailing his/her weapon about randomly with every step, hoping to hit an undetected monster by accident. In NetHack, attempting to move onto a square containing an undetected monster (and not marked by the game as suspected of containing a monster) prints an unseen monster detection message, reveals the monster if the player would be able to see a non-hiding version of the monster, and otherwise wastes the turn - perhaps the player bumped into the monster. I think this is the ideal way to handle unseen monsters, whether they be invisible, in a dark room, etc., and regardless of whether they are hostile or not. This also makes the monster hostile in NetHack, which does not make so much sense to me, either gameplay- or flavor-wise.

This doesn't only apply to invisibles, but also to blindness and darkness. Ever had to lead the cute puppy through a dark room?

I think the best solution would be to promt only the first time you bump into an unseen enemy ("Attack the invisible creature (y/n)?") and want to attack it. If you answer "yes", the NPC is flagged and any following bumps will result in an attack. If "no", it remains unflagged and the player will be promted again if he bumps into it. This allows the player to change his mind and attack an invisible creature that he didn't want to earlier.

Agreed. Accidentally bumping into something you didn't know was there is not the same thing as swinging your flaming eternium two-handed sword of devastation at it, and there should be some sort of prompt. Otherwise you just end up with the complications that arise from accidentally killing things through no fault of your own, in a scenario that wouldn't happen anyway if the situation was real (because in real life, you get to decide whether to attack or not).

This also should be applied to darkness & blind state.

... In real life, no one is invisible. Though I guess your point is that if one were to be invisible in real life, they wouldn't interpret being bumped into as a sign of aggression.

I don't think there should be a prompt, but I do think that the PC's tactic should influence what happens. If you're in Coward mode, you're not going to be swinging your sword around in front of you. Bumping into a non-hostile invisible being while in Coward should never attack (although some such beings might become hostile due to being bumped - I wouldn't include Khelavaster amongst those, though).

Now, I could be mistaken, but doesn't wearing shields only prevent the PC from attacking, anyway? So if you're going into Terinyo after saving Khelavaster, you should be safe so long as you're not wielding your weapon - as a work-around until some more direct way to prevent attacking invisible beings is implemented.

This. And this.

I don't see any reason to defend the current behaviour. Yes, there are times where the most realistic option isn't the most playable/fun option, so the best thing to do is to be unrealistic. But this is not the case. Laukku's suggestion would make the game not only more realistic, but also more playable.

Come on, in real life we don't have invisibility but we do have darkness and blindness. If things worked like in ADOM, going to drink some water at night and stumbling into another family member in the dark would mean receiving a punch to the face. And being grateful that they weren't holding a knife to make a sandwich :)

A solution that would also fix this issue was presented in the comments for

http://www.adom.de/forums/project.php?issueid=1333

Essentially, tie it into the Tactics setting. Walking around on aggressive or higher means attacking spaces into which you walk; otherwise, not.

Yes, that's what I meant. There was an implicit "given that it were real" implied. And not just that the invisible party wouldn't automatically interpret it as a sign of aggression, but also that the non-invisible party wouldn't automatically start swinging like a maniac.

ROFL, that's awesome! :D

Characters in ADOM are very paranoid, they always swing before stepping. Maybe the creator can just add 'do-not-swing' to the Coward tactic setting, like mentioned. You can still kick/shoot if you must attack somthing in coward. Alternatively 'F8' can be 'Coward-without-attack' tactic setting.

Actually, I'm pretty sure characters in ADOM come from a tremendous variety of cultural backgrounds and professions (race/class/alignment ring a bell?) and would have wildly different dispositions. And even in a world like Ancardia, someone who swung their weapon randomly in the air before every step they took would look... well... crazy.

If you never attacked an invisible being you will be prompted on whether you wanted to attack.

Oh, and Khelevaster should not cast invisibility on himself without good reason :-) I never intended him to be invisible by default...

That made my day :D

Hah, what a surprise to find that invisible Khelevaster is a bug!

Wow, this is shocking! I think this bug has become some sort of ADOM sign and should stay!

In retrospect it makes very little sense for him to be invisible. Why have we never questioned this before? :/

I always thought that he either 1. was paranoid after the chaos servant attack and wanted to hide from any potential danger, 2. only wanted the worthy (no one else in Terinyo than the player can potentially see invisible) to be able to find him again.

Or, from an out-of-universe point of view, 3. to complicate the finding of the TotRR. But now that everybody has known about it for over a decade, that is pointless by now.