blink + invisibility = miss chance?

[Theo R Cwithin]

My head is swimming thinking about this.

What is the miss chance for an attack against a creature that has both an invisibility and a blink effect up?

I don't think this is clear by RAW, and I have a feeling how I'd rule... but I'd like to see other opinions. Or if sbdy can point me to a faq or something official, that would be great, as well.

FWIW, here's my interpretation:
[sblock]
The miss chance for invis and blink arise for different reasons: Miss chance for invis arise because target can't be seen.

invis has miss chance 50%
- see invis reduces this to 0%

Miss chance for blink arises partly because target changes between seen/not seen, and partly because sometimes target changes between physically there/not there.

blink has miss chance 50%
- see invis reduces this to 20%
- ghost touch reduces this to 20%
- both see invis + ghost touch reduce this to 0%

For this reason, I think the miss chance for the two effects ought to stack, at least to a degree.

I suspect the RAW interpretation is that invis+blink gives a 50% miss chance, regardless. However, this means for two attackers without see invis, the one with a ghost touch weapon is just as likely to hit as the one without. I think the ghost-touch weapon ought to give an advantage, call it 30% to be consistent with the above numbers. So I am ruling:

blink + invis has miss chance 80%
- ghost-touch reduces this to 50% (same as for normal weapon vs invis.)
- see invis reduces this to 20% (normal for blink-only case)
- see invis + ghost touch reduce this to 0%

Well, there it is. Apologies if it's a a bit confusing to read; I just threw it out there without much editing.
[/sblock]

 

[Dandu]

50% miss chance from Invisibility, further 50% miss chance from the blinking effect?

 

[StreamOfTheSky]

Wow, Blink has wonkier text than I remembered. Why the heck does seeing invisibility help against it at all? I also don't see the rationale in ghost touch weapons not always working. Just read this line about one of the drawbacks: "Likewise, your own attacks have a 20% miss chance, since you sometimes go ethereal just as you are about to strike."

As far as I can tell, at any split second, you're either on the material plane or the Ethereal plane. If there is a sort of limbo-esque "transition" stage where you're on neither, I guess that would explain things, but I don't think that's how it works. So...if a ghost touch weapon is used, either by the caster or against the caster...the miss chance should be 0%. Either the caster is on one plane or the other. Ghost touch hits on both planes. End of story.

On the other hand, being ethereal also makes you invisible. I still think caster + ghost touch weapon = no miss chance. For the case of attacking the caster with a ghost touch weapon...I still don't buy the concealment explanation. He's clearly in the one spot, and blinking rapidly enough that you can determine where in the square he is and isn't, the miss is happening in case he pops out of the plane when you strike. But if you have a ghost touch weapon, that doesn't matter.

Since being ethereal includes going invisible, I don't think invisibility adds anything at all to the Blink spell. It'd be a waste to have both running simultaneously.

 

[Vegepygmy]

50% miss chance for concealment + 20% miss chance for not being there at all = 60% miss chance.

(This is not official, of course.)

 

[Vegepygmy]

Why the heck does seeing invisibility help against it at all?

Because ethereal creatures are invisible. If you can see invisible things, you can at least see the blinking creature 100% of the time, even though you can only hit it 50% of the time (when it is on the same plane as you).

I also don't see the rationale in ghost touch weapons not always working.

What's this about ghost touch weapons not working? I don't see anything in the spell description about that.

If the attack is capable of striking ethereal creatures, the miss chance is only 20% (for concealment).

So if you have a ghost touch weapon, but can't see invisible things, 20% miss chance. Right?

He's clearly in the one spot, and blinking rapidly enough that you can determine where in the square he is and isn't, the miss is happening in case he pops out of the plane when you strike. But if you have a ghost touch weapon, that doesn't matter.

Oh, I see where the confusion lies.

First of all, the blinking can't be happening that rapidly. Since a blinking creature can pass through walls, it must be able to move quickly enough that you can't say just because you saw him in one square a moment ago, he's still there when you attack.

Second, and much more importantly, the game is attempting to model the confusion that would arise from only being able to see your opponent 50% of the time. Imagine, for example, that you were fighting someone in a room illuminated only by a strobe light. Despite the fact that your opponent is always on the same plane as you (effectively the same as a ghost touch weapon vs. an ethereal opponent), it would be harder to actually land a blow. Not as hard as in a pitch black room (invisible opponent = 50% miss chance), but certainly your opponent would benefit from some degree of concealment (say, 20%).

 

[Theo R Cwithin]

Wow, Blink has wonkier text than I remembered.

Hehehe... well, I'm glad I'm not the only one who thinks this is wonky

One thing blink does is to cause the blinker to be seen/unseen; I liken it to a strobe light. Yes, you know where he is, but you can't anticipate well because his movements are broken up; it's effectively "poor lighting". I think that's a valid concealment20%, and makes sense for the case of "can't see invis but has a ghost touch weapon".

The other thing blink does is cause the blinker to be here/not here as the blink hops in and out of the Ethereal. In the spell, this seems to be equated to a "partially incorporeal" effect, and hence the 20% miss chance if you can see invis but can't ghost-touch.

And apparently these two types of miss chances somehow combine into a total miss chance of 50%.


Now if the blinker is invisible, then the "poor lighting" effect of blink is overridden by the "no lighting" effect of invis, and thus he gets concealment50% for that. It just seems to me, though, that a blind attacker with a ghost-touch weapon should have a better shot of "accidentally" hitting than the blind attacker without a ghost-touch weapon. And so wouldn't the invisible blinker therefore have a better miss chance against the blind guy with a mundane sword than against the blind guy with a ghost-touch sword (eg 80% and 50%, respectively)?

Oh well, I suppose the easy thing to do is to just say invisibility doesn't give any advantage to a creature already blinking. *grumble* But that doesn't make sense to me.

Anyway, thanks for the responses!


BTW, on a related note:

What's the miss chance on an invisible (miss 50%) incorporeal (miss 50%) creature??? Is it 75%, 80%, 100%?

Surely this comes up now and then? Shadows in pitch dark conditions? Wraithes with greater invisibility?

 

[Theo R Cwithin]

50% miss chance for concealment + 20% miss chance for not being there at all = 60% miss chance.

(This is not official, of course.)

Oh cool! So there is some agreement that a miss chance >50% is possible. It certainly seems logical, though I get the impression there's no official ruling. Thanks for the number; perhaps my initial guess of 75% or 80% was too high.

In my last post, I ended with the miss chance on an invisible incorporeal creature. Any thoughts on that one?

 

[Michael Silverbane]

I don't recall the source, but I believe that when combining miss chance from different sources, you check separately against each one.

So... Invisibility = 50% miss chance and blink = 50% miss chance, you check twice.

 

[Dandu]

Invisible, Blinking: 50% miss chance for invisible. Roll to determine a hit or miss. If hit, there's a 50% chance that that hit still misses due to blinking on and off the material plane.

 

[irdeggman]

Rules Compendium

pg 32
"Concealment"

"multiple concelament conditions don't stack. If a creature receives miss chances from multiple sources, such as from being incorporeal and having concealment, only the highest miss chance applies."


pg 51
"Etherealness"

"Unlike incorporeal creatures, ethereal creatures aren't present on the Material Plane."

"Ethereal creatures are invisible, inaudible, insubstantial, and scentless to creatures on the Material Plane."

"See invisibility and true seeing reveal etheral creatures. Even if a creature on the Material Plane can see an ethereal creature, the ethereal creature in on another plance."

pg 64
"Incorporeality"

"If a creature receives miss chances from multiple sources, such as being incorporeal and having concealment, they don't stack. Only the highest miss chance applies."

Blink (from SRD)

"Physical attacks against you have a 50% miss chance, and the Blind-Fight feat doesn’t help opponents, since you’re ethereal and not merely invisible. If the attack is capable of striking ethereal creatures, the miss chance is only 20% (for concealment).

If the attacker can see invisible creatures, the miss chance is also only 20%. (For an attacker who can both see and strike ethereal creatures, there is no miss chance.) Likewise, your own attacks have a 20% miss chance, since you sometimes go ethereal just as you are about to strike."


So it appears that blinks causes you to be on another plane 20% of the time - which means that you can't interact with things on the Material Plane during that time (except via ghost touch or force type attacks).

Opponents have a 50% miss chance (but 20% of that is specifically from concealment) - so a 30% miss chance, except that it specifies that the miss chance is 20% even if they can see you (i.e., negates the concealment). Really poor math, but probably done for "simplicity" and not accuracy.

So since concealment does not stack:

I would say that an invisible, blinking creature has a 50% miss chance (from total concealment and can't be attacked at all unless the square it occupies is known) - whereas a blinking (not invisible) creature can be attacked with a 50% miss chance - since you can determine what square it is in. This miss chance goes to 20% if the opponent can see invisible.

Basically no additional miss chance from being invisible, only a harder time being found.