Does being invis stop AoO?

[jontherev]

I've pointed this out before, but, whether or not you know they are casting a spell is just about irrelevant, because you have no way of knowing if they are casting on the defensive.

DM: You hear someone casting a spell right next to you.
Player: I take my AoO.
DM: Not so fast slick, he's casting on the defensive, but go ahead and mark of that AoO for the round - you missed.

If that's the case, the DM should say, "You hear someone casting a spell right next to you (let's assume he didn't hear the caster approach, so he must have either teleported or has rogue levels or something), but you don't realize it until it's too late." Casting on the defensive does not provoke AoO's, so you can't lose your attempt for the round in the scenario you gave.

 

[jontherev]

I don't believe you can take an AoO on an invisible person wether or not you know there is an invisible person there unless you
a) know the invisble person is present
b) know the 5' square the invisible person is in
c) know the invisible is doing something that provokes an AoO

The AoO would suffer from 50% miss chance regardless.

This means, with some listen checks, you might get to AoO a person casting a spell, but would almost never get to AoO a person who was grappling, because you would need to know about it before the result actually happens.

Robaustin, your case only covers part of these needs. I don't think this is too complicated. What is the listen DC to pinpoint a person to a square? If the person can't possibly make it, you don't even have to worry about this.

You can quite easily take an AoO on an invisible foe trying to grapple you. That invisible dwarven fighter in fullplate makes a boatload of noise, which will easily be picked up by a Listen check. Look at the DMG for rules on the proper Listen DC. I believe it is 0 (while in combat) + 20 (to pinpoint exact square) = 20 to spot (via Listen) the exact location of an enemy who moves vs. their Move Silent check. For stuff like whipping out a potion, uncorking it, and drinking it while 5' away from an enemy, I'd use a similar rule, though nothing official exists to my knowledge.

Invisibility does not provide you with an infinite Move Silent skill. Now, in conjunction with a Silence spell...

 

[RigaMortus]

If that's the case, the DM should say, "You hear someone casting a spell right next to you (let's assume he didn't hear the caster approach, so he must have either teleported or has rogue levels or something), but you don't realize it until it's too late." Casting on the defensive does not provoke AoO's, so you can't lose your attempt for the round in the scenario you gave.

And how would you handle it if the invisible person "bluffed" casting a spell. He said all the correct magic words (Abracadabra) and what not. How does someone know if he is really casting the spell or just talking? You don't provoke AoOs for talking, do you?

 

[Chauzu]

Unless the attacker can sense them some how through smell, hearing, or whatever, yes, being invis does stop AoO. That is how I do it whether it is in the book or not.

 

[jontherev]

And how would you handle it if the invisible person "bluffed" casting a spell. He said all the correct magic words (Abracadabra) and what not. How does someone know if he is really casting the spell or just talking? You don't provoke AoOs for talking, do you?

Why in the world would an invisible caster want to reveal his location by bluffing to cast a spell? If you cast on the defensive, you don't provoke an AoO period...whether the caster is invisible or not is irrelevant. However, you can still give the guy a Listen check to notice the not-so-smart invisible caster talking/bluffing nearby, and if he doesn't hear the caster move away right after that (using the Move Silent/Listen check IF he does move), he'll be able to full attack him on his next turn, suffering only the 50% miss chance, assuming he made the Listen check to notice him talking/bluffing. Not a tactic I would ever use.

 

[Cyraneth]

Well, how would one know he got a chance at an attack of opportunity against an invisible opponent before it was too late? A grappling plate-wearing dwarf might as well make the noise trying to attack with his axe, while a wizard might as well cast his spell on the defensive. Not being able to see his attacker, the defender wouldn't have a chance at guessing what his opponent was doing, let alone see an opening in the attacker's defense.

Merely my coppers' worth...

- Cyraneth

 

[LokiDR]

You can quite easily take an AoO on an invisible foe trying to grapple you. That invisible dwarven fighter in fullplate makes a boatload of noise, which will easily be picked up by a Listen check. Look at the DMG for rules on the proper Listen DC. I believe it is 0 (while in combat) + 20 (to pinpoint exact square) = 20 to spot (via Listen) the exact location of an enemy who moves vs. their Move Silent check. For stuff like whipping out a potion, uncorking it, and drinking it while 5' away from an enemy, I'd use a similar rule, though nothing official exists to my knowledge.

Invisibility does not provide you with an infinite Move Silent skill. Now, in conjunction with a Silence spell...

You know the fighter is around and close. You can't see him, so he must be invisible. Let's even assume you made a listen check to located the 5' square he is in. Now tell me, how are you know he is going to grapple?

The grapple starts with a touch attack that provokes an AoO. Do know that is a touch attack coming, or maybe just an axe. The attacker gets the +2 to attack you and you are denied your dex bonus. But somehow you can react to grapple by attacking before the grapple touch attack even lands. I don't buy that.

 

[Hypersmurf]

The grapple starts with a touch attack that provokes an AoO. Do know that is a touch attack coming, or maybe just an axe. The attacker gets the +2 to attack you and you are denied your dex bonus. But somehow you can react to grapple by attacking before the grapple touch attack even lands. I don't buy that.

The turn-based mechanic of combat rounds is a representation of simultaneous action. The approach of the invisible attacker prompts a violent response on the part of the defender. If it's an axe, then the combat mechanic provides no chance for that violent response to have a game effect. If it's a grapple, the combat mechanic represents the chance of that violent response causing damage as an AoO.

-Hyp.

 

[Surefoot]

To simplify things I would say you get an attack of opportunity against an invisible opponent only if you know what square he's in.

 

[jontherev]

You know the fighter is around and close. You can't see him, so he must be invisible. Let's even assume you made a listen check to located the 5' square he is in. Now tell me, how are you know he is going to grapple?

The grapple starts with a touch attack that provokes an AoO. Do know that is a touch attack coming, or maybe just an axe. The attacker gets the +2 to attack you and you are denied your dex bonus. But somehow you can react to grapple by attacking before the grapple touch attack even lands. I don't buy that.

Why not? You hear someone entering your square (make your Listen check) and take a swing in that direction. It's debatable whether it's the touch attack or the movement into the square that causes the AoO...the "why" or "how" is not spelled out in the rules afaik. Bullrush uses a similar mechanic to grapple in the case of the AoO, but actually spells out that it's the movement that causes the AoO...and that leads me to believe it's the same with grapple. But it's irrelevant in any case. If you make your Listen check by 20, you know he's within a few feet of you and it doesn't matter what weapon he's brandishing, unless he used tumble or spring attack and you've ruled that it's the touch attack that causes the AoO (BTW, if this has been clarified, please let me know). It's up to the DM to let the player know whether or not he will be able to take an AoO (i.e. the enemy has tumble, spring attack, or is casting on the defensive, etc.). Bottom line is this...if the invisible guy provokes an AoO, and his enemy has some way of detecting the action causing it (by making an appropriate Listen check), then the only defense invisibility provides in this case is the 50% concealment and immunity to sneak attacks. IMO, invisibility is not meant to provide immunity to AoO's.