CR deduction due to permanent blindness

[heavyfuel]

If a creature were to be permanently blinded, how much would his CR be reduced by? By RAW, probably by zero. But realistically, just how much easier would it be to beat the blind creature?

[atemu1234]

Perhaps one or two lower, mostly due to the 50% miss chance.

[heavyfuel]

Perhaps one or two lower, mostly due to the 50% miss chance.

Sure, every creature having Total Concealment is the big one, and that alone is probably worth a -2. But there's also the effective -4 to AC (-2 from blindness, enemies get +2 from being hidden), the loss of Dex bonus to AC which may reduce it even further, but more imporantly, makes you vulnerable to Sneak Attacks 100% of the time, and because you're not flat-footed, it can't even be negated by Uncanny Dodge. Only being able to move at half your move speed will probably make you very kite-able.

The SRD says that a creature that remains blind for a very long time can learn to overcome some of these drawbacks, but it's left entirely up to the DM just how much is overcome.

[Jack_Simth]

If a creature were to be permanently blinded, how much would his CR be reduced by? By RAW, probably by zero. But realistically, just how much easier would it be to beat the blind creature?
I think it depends pretty heavily on the specific creature.

A creature with Blindsight is going to be a lot less inconvenienced than is a creature with blindsense, which is in turn less inconvenienced than a creature without either.
A creature with automatic abilities that hurt attackers (e.g., a Babau's slime) is going to be less inconvenienced that is a creature that can only hurt others actively.
A creature that relies primarily on targeted abilities is going to be considerably more inconvenienced than is a creature that relies primarily on area effects.

So that Wizard-3 that only prepared Magic Missile, Charm Person, and Scorching Ray today (theoretically CR 3)? Cakewalk CR 1/2 (pretty much incapable of fighting back). That Very Young White Dragon (also theoretically CR 3)? Considerably less so (Blindsense to locate you, breath weapon to make you chill out, and enough attacks that it's likely to land one each round even without blind-fight to reduce the miss chance) - call it CR 1 if it doesn't have blind-fight, CR 2 if it does.

[Urpriest]

I'd just include the character who blinded the monster in the party for XP calculations, or if they don't have an ECL instead use their CR and subtract off the amount of XP defeating them would grant.

[The Great Wyrm]

There's a blind Mountain Troll in the Slaughtergarde premade adventure. I know it's not the normal CR; maybe 2 or 3 lower.

[Tvtyrant]

There's a blind Mountain Troll in the Slaughtergarde premade adventure. I know it's not the normal CR; maybe 2 or 3 lower.

This seems bad to me. Mountain trolls are big piles of hit points and damage, so it just trades TPK for "unlucky character gets instantly killed, no one else gets hit."

[Crake]

it can't even be negated by Uncanny Dodge.

Actually, it can, because all people attacking you are treated as "invisible" opponents, and uncanny dodge works against invisible attackers as well as while flat footed.

[heavyfuel]

I think it depends pretty heavily on the specific creature.

A creature with Blindsight is going to be a lot less inconvenienced than is a creature with blindsense, which is in turn less inconvenienced than a creature without either.
A creature with automatic abilities that hurt attackers (e.g., a Babau's slime) is going to be less inconvenienced that is a creature that can only hurt others actively.
A creature that relies primarily on targeted abilities is going to be considerably more inconvenienced than is a creature that relies primarily on area effects.

So that Wizard-3 that only prepared Magic Missile, Charm Person, and Scorching Ray today (theoretically CR 3)? Cakewalk CR 1/2 (pretty much incapable of fighting back). That Very Young White Dragon (also theoretically CR 3)? Considerably less so (Blindsense to locate you, breath weapon to make you chill out, and enough attacks that it's likely to land one each round even without blind-fight to reduce the miss chance) - call it CR 1 if it doesn't have blind-fight, CR 2 if it does.

Sure, it most certainly does. But what if we assumed that blindness is a template of sorts? Some templates are great for some creature and terrible for others, so some have variable CRs, like the Dark Creature template. What would be a good guideline? I think from -1 to -4 is about good, though I could be way of.


I'd just include the character who blinded the monster in the party for XP calculations, or if they don't have an ECL instead use their CR and subtract off the amount of XP defeating them would grant.

What if it wasn't a creature that made them go blind? Like, if they were born blind.

[heavyfuel]

Actually, it can, because all people attacking you are treated as "invisible" opponents, and uncanny dodge works against invisible attackers as well as while flat footed.

Not really. The creatures are treated as invisible, sure, but the thing is that "Blind" specifies that a creature loses its Dex bonus to AC as part of the condition, and Uncanny Dodge doesn't get around that, similarly to how UD won't stop loss of Dex bonus to AC due to an enemy feinting you, or from being tied up or paralyzed.

[Jack_Simth]

Sure, it most certainly does. But what if we assumed that blindness is a template of sorts? Some templates are great for some creature and terrible for others, so some have variable CRs, like the Dark Creature template. What would be a good guideline? I think from -1 to -4 is about good, though I could be way of.The things with variable CR increases have them because the template itself scales - The Celestial Creature template, for instance, gives different quantities of DR, SR, and energy resistance based on hit dice. Trouble is, blindness doesn't work the same way. Any guideline comprehensive enough to be particularly useful is going to be complex enough that you might as well just say "eyeball it".

[Crake]

Not really. The creatures are treated as invisible, sure, but the thing is that "Blind" specifies that a creature loses its Dex bonus to AC as part of the condition, and Uncanny Dodge doesn't get around that, similarly to how UD won't stop loss of Dex bonus to AC due to an enemy feinting you, or from being tied up or paralyzed.

ah yeah, you're right, i always thought they lost their dex to AC by virtue of all their attackers being invisible.

[heavyfuel]

The things with variable CR increases have them because the template itself scales - The Celestial Creature template, for instance, gives different quantities of DR, SR, and energy resistance based on hit dice. Trouble is, blindness doesn't work the same way. Any guideline comprehensive enough to be particularly useful is going to be complex enough that you might as well just say "eyeball it".

But Dark creature doesn't have any such a scale. So I was really hoping for a CR adjustment that would at least help eyeball it.


ah yeah, you're right, i always thought they lost their dex to AC by virtue of all their attackers being invisible.

:smallwink:

[Ashtagon]

I'd just include the character who blinded the monster in the party for XP calculations, or if they don't have an ECL instead use their CR and subtract off the amount of XP defeating them would grant.

What if it was a freak accident involving a stalactite and an uneven cave floor?

[atemu1234]

What if it was a freak accident involving a stalactite and an uneven cave floor?

I remember something to do with terrain CRs, somewhere.

[Hamste]

What if it was a freak accident involving a stalactite and an uneven cave floor?

Obviously it was an incident between a stalagmite and a confused roper

[Jack_Simth]

But Dark creature doesn't have any such a scale. So I was really hoping for a CR adjustment that would at least help eyeball it.And it even tells you why - of course, what the Dark creature template pretty much says is "eyeball it".

Really, though, you've got three things to look at: Senses, Offence, and Defence.

Senses:
If the blindness completely neuters their senses to the point where the creature doesn't have a way to pinpoint what square an attacker is in, then the critter is pretty much toast. It's target practice for anyone with a bow that behaves intelligently. Call this -3 CR.
If the blind creature still has a reasonably reliable way to pinpoint what square an attacker is in (Blindsense, Tremorsense, a really good Listen check, and similar abilities) and you can be reasonably sure that the party will be within this range then it's at least got a chance of fighting back. -1 CR. If they won't be within that range, then you're looking at "doesn't have a way to pinpoint" at -3.
If the blind creature can still tell exactly where someone is (Blindsight and related), then it's really not a penalty to the creature if the party is going to be in the range of said ability. -0 CR.

Offence:
If the blindness completely neuters the creature's primary ability to attack (e.g., all of it's useful combat abilities are targeted in the same way that Magic Missile and Charm Person are), then the critter is pretty much toast. It's harmless to anyone with a bow that behaves intelligently. Call this -3 CR.
If the blindness causes a heavy miss chance to the creature's primary ability to attack (e.g., it does NOT have blind-fight, and has to make attack rolls) without completely neutering it, then it's arbitrarily missing half the time, and takes half the resources to take down - which is pretty much the definition of -2 CR.
If the blindness causes a light miss chance to the creature's ability to attack (e.g., it has Blind-fight, and makes attack rolls), then it's arbitrarily missing about 25% of the time, and takes about 3/4ths the resources to take down - which is about -1 CR.
If the creature's primary ability to attack uses some method that's not noticeably impacted by the blindness (e.g., area spells, dragon's breath weapon, automatic return fire from an Ooze's slime), then the creature's primary ability to attack is unaffected by the blindness: -0 CR.

Defence:
If the creature doesn't have a way to avoid blows effectively due to the blindness (as in, it doesn't retain it's dexterity modifier vs. an attacker, and that was five or ten points of it's AC) then it's a LOT easier to take down. Call it about -1 CR for every three or four AC lost.

So that Elf Wizard-6 with a Dex of 18, no ranks in listen, who only had targeted spells prepared, no scrolls or wands that are useful, and is suddenly struck blind... is sitting at -6 AC (-1 or -2 CR), no useful offence (-3 CR), and no way to pinpoint an attacker (Listen at +2 doesn't help - -3 CR) is about CR 1/3rd. If said creature was instead a Druid-6 with Natural Spell, it could Wildshape into a hunting bat, pick up Blindsense, and start Summoning creatures to kill you. Said Druid is down a few points of AC (so -1 CR), can locate you reasonably well (but not blindsight, so -1) and has a decent primary attack available that's unaffected by the blindness - so CR 4 (not counting the animal companion, which can still wreck you anyway - Druids are mean).