Why are attacks and afflictions viewed oppositely by GURPS assumptions?

[awesomenessofme1]

Attacks: Totally OK to make them completely unavoidable (a little expensive, given you need +700% worth of Cosmic, but it's explicitly called out as a thing you can do). Totally impossible to make yourself completely immune (book says it would cost infinite points).

Afflictions: Totally OK to make yourself completely immune (not even that expensive, 30 points maximum for a wide range of effects). Totally impossible to make them completely unavoidable (the official FAQ refers to the idea as "grand ultimate munchkin stuff").

So what's the difference? I have no doubt that there were reasons for these opposite assumptions being baked into GURPS, but they don't come to me right away. After all, both complete immunity to (at least some forms of) damage and completely irresistible status effects are quite common in fiction and other games, so there would have to be reasons for the situation.

[RyanW]

Well, an unavoidable attack is really "always hits, ignores armor" which you can also add to an affliction. The only difference is that an affliction requires an attribute roll instead of a damage roll. Attribute rolls are, in general, more bound than damage (it's rare to see modifiers beyond +/-10, while 1d-2 and 6d*100 can easily show up in the same turn). So the game is much more tolerant of "can automatically succeed at specific attribute rolls" than it is to "completely ignores specific sources of damage" as a finite trait.

[nudj]

Unavoidable damaging attacks are still "resisted" by hit points or Damage reduction (Injury tolerance).

Afflictions can be "resist or I win". So you need to keep the resistance roll.

[Varyon]

I could see cause for something like No Nuisance Resistance for making it so that, as long as the target's resistance is below 3, they don't get a roll. That still requires you to have sufficient levels of Affliction (or sufficient damage from an Innate Attack with Side Effect) to penalize their resistance to below 3, but then again, going with what nudj noted, killing someone outright with a damaging attack requires you to have sufficient damage to get their HP to -1xHP (or maybe even -5xHP if you want them to not get a roll). Seeing as it basically just takes them from a ~1.5% chance to resist to 0%, it's probably not a huge Enhancement value, maybe +10%.

If you want immunity to damage to be a thing, honestly I think it could fit alright with GURPS, you just need to add a new Enhancement (probably a Cosmic one) that allows you to ignore said immunity (just like Affects Insubstantial lets you ignore that form of immunity). If you want an eyeballed value for Immunity to Injury, go with [250]. I'll note I came up with this based on the fact that changing Armor Divisor to scale with SSR matches close to the current prices if it costs +30% per level, and normally the cost of 10 such levels would therefore match the value of Ignores DR. Meanwhile, IT:DR already scales with SSR (there's the oddity of adding a divisor of 4 between 3 and 5, and then skipping the divisor of 7, but beyond that it's straight SSR), and 10 levels of that would cost [250]. Ignoring it is probably worth something like +100% (arguably, by comparison to Affects Insubstantial +20% negating Insubstantiality [80], it should be closer to +60%, but +100% feels more right).

[Fred Brackin]

Originally Posted by Varyon

If you want an eyeballed value for Immunity to Injury, go with [250]. I'll note I came up with this based on the fact that changing Armor Diviso.

Alternatively you could go with Unkillable 2 and Extreme Regeneration also for (250). You can go unconscious and even sort of/kind of "die" but it never lasts more than 10 seconds.

This is might be how I'd do a lot of "invulnerable" heroes. For only "nigh invulnerable" like The Tick you could go down to the 50 pt version of Regeneration. This would model how Proto-Clown could knock him into a sub-orbital flight but The Tick is alright again by the time he lands.

[Anders]

The way you make an Affliction impossible to resist is to buy many many levels of it. 8 levels means normal people don't even get to roll.

[Anders]

Originally Posted by Varyon

If you want an eyeballed value for Immunity to Injury, go with [250].

That's pretty close to the 3e value of 300 points. I think it's in the right ballpark.

[Varyon]

Originally Posted by Fred Brackin

Alternatively you could go with Unkillable 2 and Extreme Regeneration also for (250). You can go unconscious and even sort of/kind of "die" but it never lasts more than 10 seconds.

Yeah, you can do some impressive stuff with Unkillable 2/3 and a high level of Regeneration.

Originally Posted by Fred Brackin

This is might be how I'd do a lot of "invulnerable" heroes. For only "nigh invulnerable" like The Tick you could go down to the 50 pt version of Regeneration. This would model how Proto-Clown could knock him into a sub-orbital flight but The Tick is alright again by the time he lands.

The Tick - at least the cartoon version, which is the only one I'm really familiar with - always strikes me as a really good example of IT:DR. His version may have a Limitation on some or all of it that attacks still deal their full shock penalty - he doesn't really seem much less susceptible to pain from stuff like getting punched in the face (although that's largely played up for comedic effect). Some degree of Regeneration does seem like a given, however.

Originally Posted by Anders

The way you make an Affliction impossible to resist is to buy many many levels of it. 8 levels means normal people don't even get to roll.

I had thought Resistance Rolls had the same rule as Defense Rolls, that you can still attempt them even when they're below 3 (but need a 3 or 4 to accomplish anything), but checking it again I see that's not actually the case. So, no need for a No Nuisance Resistance Enhancement - getting the target's resisting attribute below 3 is enough on its own to make the ability irresistible.

Originally Posted by Anders

That's pretty close to the 3e value of 300 points. I think it's in the right ballpark.

[300] probably works too. [250] does have the small advantage of having a bit more pleasing of a progression for Rare vs Uncommon vs Common vs Very Common vs Unlimited - for the former, these are worth [60], [120], [180], [240], and [300], respectively, while for the latter they are instead [50], [100], [150], [200], [250]. In any case, having some sort of Cosmic "Ignores Immunity" effect available is generally going to be necessary to have it work properly, and typically requiring Limited Defenses be in play is probably a good idea.

[David Johnston2]

Originally Posted by awesomenessofme1

Attacks: Totally OK to make them completely unavoidable (a little expensive, given you need +700% worth of Cosmic, but it's explicitly called out as a thing you can do). Totally impossible to make yourself completely immune (book says it would cost infinite points).

Afflictions: Totally OK to make yourself completely immune (not even that expensive, 30 points maximum for a wide range of effects). Totally impossible to make them completely unavoidable (the official FAQ refers to the idea as "grand ultimate munchkin stuff").

So what's the difference? I have no doubt that there were reasons for these opposite assumptions being baked into GURPS, but they don't come to me right away. After all, both complete immunity to (at least some forms of) damage and completely irresistible status effects are quite common in fiction and other games, so there would have to be reasons for the situation.

You can render yourself totally immune to mundane physical attacks using insubstantiality. And that's the point. You are immune when you are insubstantial because you are no longer interacting with the attack at all. You aren't getting hit. The robot who is immune to metabolic attacks is also not interacting with the attack. You can't interfere with the blood flow of an entity that has no blood. Nor is it true that complete immunity to damage is common because it is impossible to determine that a character is completely immune without them having an ability that makes it impossible to hit them. At best all you can do is say "They haven't been hit hard enough to hurt them...yet." The possibility always exists that some even stronger attack exists or can be created that can do some damage.

[Fred Brackin]

Originally Posted by Varyon

The Tick - at least the cartoon version, which is the only one I'm really familiar with - always strikes me as a really good example of IT:DR.

Nah, The Tick (and I definitely the cartoon version) is sometimes Stunned by attacks to his weak point (i.e. his head) but doesn't show any effect from attacks anywhere else.