I'm going to start with advice for everyone: use some resources before posting 'bug' reports. The NWN Wiki site in particular. Threads like these posted in the Problem Reports forum give the wrong impression that something is broken when it is not, which I do not appreciate. There are enough real bugs to deal with without creating phantom bugs as well!
So to put out a fire that should not have started in the first place, read the following which is available on the wiki site, especially the bold part:
Do you think assassins would be extremely alert when hunting their prey? YES. Do you think they are skilled at not only moving stealthy but being very aware of their environment? YES. Is it likely other creatures you encounter are vigilant as well? YES. Do you think that casting an invisibility spell when surrounded by enemies is a 'get out of trouble free card'. NO. More often than not one of them is going to hear you, or will, the longer you stick around - especially if they were targetting you in combat or you cast it when they are right next to you.
So to make things crystal clear here: this is not a bug; therefore I am moving this out of the Problem Reports forum.
So to put out a fire that should not have started in the first place, read the following which is available on the wiki site, especially the bold part:
Quote:Invisible creatures cannot be seen by non-magical vision. They cannot be detected with the spot skill, but can be detected with listen. If heard, they are rendered translucently on the game screen and can be attacked. Invisibility inherently grants 50% concealment, and anyone attacked by an invisible creature is considered flat-footed. Furthermore, invisible creatures receive a +2 attack bonus unless negated by the target's blind fighting. Attacking, or performing any hostile act, causes invisibility to be lost, though. This includes hostilities performed by a lingering spell (cast by the subject before becoming invisible), but does not include summoning a creature nor hostile actions taken by a summoned creature.
The types of magical vision that can see invisible creatures are see invisibility and true seeing. These types of magical vision also negate the +2 attack bonus granted by invisibility, but (probably a bug) they negate the bonus when the invisible attacker has them, rather than when the target of the attack has them. See invisibility and true seeing also negate the concealment inherent to invisibility (but not other types of concealment; in particular, improved invisibility has a separate 50% concealment effect that is not negated).
Attacking a creature that cannot be seen gives a -4 penalty to attack rolls. In particular, this usually applies when attacking an invisible creature.
Since some creatures can detect or even see invisible creatures, it can be helpful to use stealth mode even when invisible.
Do you think assassins would be extremely alert when hunting their prey? YES. Do you think they are skilled at not only moving stealthy but being very aware of their environment? YES. Is it likely other creatures you encounter are vigilant as well? YES. Do you think that casting an invisibility spell when surrounded by enemies is a 'get out of trouble free card'. NO. More often than not one of them is going to hear you, or will, the longer you stick around - especially if they were targetting you in combat or you cast it when they are right next to you.
So to make things crystal clear here: this is not a bug; therefore I am moving this out of the Problem Reports forum.