I have noticed that when I use a potion of invisbility within attack range of an enemy they continue to attack me after I am invisible. This is beyond any AoOs they get for me drinking a potion. If I then run away, then they will no longer attack me until I am visible again.

Is this a bug or intentional?

Regardless, I don't think it should be this way. If you are fighting something and it just instantly disappears, then I think you would probably stop attacking and try to figure out what happened.

I could see an intelligent creature reasoning out what just happened and then trying to flail out attacks in the immediate area while hoping to catch the recently disappeared foe, but only with some check or penalty. Eg. an INT check to see if the creature would know you just drank an invis potion and/or blind-fighting penalties for flailing out into empty space

Its frustrating to runaway from monsters and use the invis potion only to get caught by them and attacked after I'm already invisible (not AoOs).

The engine mechanics are allowing for for everything you just suggested, it's the gist of what is happening. It's why you still get attacked until you move away a bit.

Invisible is not undetectable. You are often times still heard and, as you say, most intelligent beings know EXACTLY what happened. They saw you drink a potion and disappear. It's not like invisibility potions are a rare and wondrous item. So, they just listen for your footsteps and swing away.

Now, once you move away from them, they lose you.

For the game mechanics, I think it's done rather realistically.

Jayde Moon is correct.

My characters, for the most part, are pretty fragile, and so I rely heavily on invisibility spells and potions to allow me to get away long enough to heal and prepare attacks, or to run up to the front-liners to render healing during combat without being pounded on. In fact, the last DM quest I was on, I went through 22 invisibility potions!

Now, I don't mind that occasionally you drink invisibility and the baddies still chase you, allowing for the fact that perhaps since they watched you go invisible, they're able to keep track of the whoosh of air, or stir of dust on the ground, or whatnot that clues them in to where you are enough to follow you.

HOWEVER, what reaaaally annoys me is when you manage to duck around a corner and go stealth to finally lose them, you go about your business doing other things until invisibility wears off, perhaps even going through a few transition points, THEN you drink invisibility and return to the scene, only to discover that the baddies that had followed you earlier instantly jump you as if you weren't invisible. Even though you were gone from the scene, completely out of sight, through a transition and back, and even on a new spell/potion of invis.

THAT really blows and is entirely unrealistic. And it happens about 1/3 of the time that you return to an area after losing them. At least, that's my experience.

It just happened to me again on my recent visit to the Curio Shop, where a group of rats followed my invisible PC until she gave them the slip. She then went down a long tunnel out of sight, passed through 2 different transition points, shopped, cast a new invisibility spell, and as soon as she came within view of those same rats on the way back, they blasted down the hall at her.

Annoying.

It's a bioware bug.

When monsters are in "chase" sequence and don't detect you going invisible, they won't realize you're invisible later if you stumble on them.

Yeah it wasn't always that way. Irritates me too.

This is why you need to buy -more- potions.

keep in mind that certain creatures have true sight or other magical means to see through invisibility.

djspectre keep in mind that certain creatures have true sight or other magical means to see through invisibility.

You should get the jump on them with Seeing potions.