Power-Disrupting Innate Attack

[Coinage]

I do think that the use of a Symptom: Neutralize with a Negated Advantage would be better, since it allows a Will save role.

The Wildcard ability is really expensive, and kind of open-ended. Reading the entry in GURPS: Supers, its kind of too open-ended for my taste.

[Coinage]

My own thinking with the "Limited by Margin" (Pyramid #3-09, pg. 16) on Neutralize is to increase the difficulty of using the specific power of a specific Power Source. So, for example, every time a target with a Innate Attack fireball attack gets a -1 on the Difficulty threshold to use the attack.

So let's say that the "Nullifier" attack hits its victim and causes 3 damage. Before that attack that victim needed to roll below a 12. However, the 3 damage causes -3 to the threshold. So, now the victim needs to roll below a 9 to successfully launch an attack.

[Plane]

Originally Posted by Coinage

Weaponized from Psionic Powers., pg. 21? That could work.
If my reading of the text is correct, neutralize just shuts down superpowers right away.
However, I was hoping for a more cumulative effect.
The more damage taken, the more difficult it is to use powers.

Powers 97 limitation "Derange" on Neutralize instead lessens control over an ability instead of completely shutting it down, making it function as if Uncontrollable (will rolls to prevent it working in weird ways)

There's also just using the Optional Crippling Rules on PP7 in place of standard crippling (far more interesting collection of possible results than merely Uncontrollable), and using the rules for Crippled Abilties on P156

P156 in paritcular under "Deliberate Crippling" has "Brute-Force Attacks" which seems to be a system related to your intent.

If damage from appro innate attack exceeds point cost there's HT to avoid cripple and if it's not all-or-nothing you might allow cumulative rolls on that table each time it fails.

[Varyon]

Do you want it to outright shutdown superpowers, or just make them more difficult to use? For the latter, I could see cause for a generic "-1 to activate powers" Disadvantage being worth between [-10] and maybe [-20], and treat any ability that doesn't require a roll as normally being a 20- to activate. Once you get those down to 16-, you start having to roll to activate. Make it a case of nested Symptoms - once you've done 1/3xHP in damage, they take a -3 to activate their powers, then another -3 at 1/2xHP, and a final -3 at 2/3xHP, for a total of -9. Or some other pattern - perhaps it's -2, then -3 (total -5), then -5 (total -10) instead.

EDIT: As an example, let's go with the -3 per step option. Symptoms at 1/3xHP injury are 3x the cost as an Enhancement on Affliction, 1/2xHP are 2x, and 2/3xHP are 1x. If going with [-20] per -1 to activate powers, that's -20% per -1 as an Enchancement on Affliction. So, on a 1d burn Innate Attack, we're looking at: Innate Attack 1d burn (1/3xHP Symptom: -3 to powers +180%; 1/2xHP Symptom: -3 to powers +120%; 2/3xHP Symptom: -3 to powers +60%) [23]. Note that would only be [14] if treating the Disadvantage as worth [-10] instead. Our -2, -3, -5 option would instead be Innate Attack 1d burn (1/3xHP Symptom: -2 to powers +120%; 1/2xHP Symptom: -3 to powers +120%; 2/3xHP Symptom: -5 to powers +100%) [22] - or [13.5] (round up to [14]) with the lower-price Disadvantage.

[Coinage]

For purposes of clarification, let's call this attack "Power-Disruption Innate Attack (PDIA)"

Okay, so if I get the ability correctly:

Treat any ability that doesn't require a roll as normally being a 20- to activate.

Once you get those down to 16-, you start having to roll to activate.

Make it a case of nested Symptoms
- once you've done 1/3xHP in damage, they take a -3 to activate their powers,
- then another -3 at 1/2xHP in damage ,
- a final -3 at 2/3xHP, for a total of -9.

Okay, this could be doable, but it would take a bit of work. The GM would have to pay attention as to how much damage is being applied to each character. That could result in a LOT of book-keeping however. Plus, the GM would have to distinguish damage caused by the PDIA from damage caused by other attacks.

I do like the idea of treat any ability that doesn't require a roll as normally being a 20- to activate. For every point of damage caused by the PDIA, lower that number. So, if the PDIA causes 4 damage, it now requires a effective skill roll of below 16 to activate.

My own inclination is to just say: Whenever the PDIA causes a certain amount of damage, the victim lowers the same number on the roll to succeed in the roll.

So, let's say that a character has an Effective Skill on Telekinesis 16. However, after the PDIA causes 4 damage, the Effective Skill Roll of 12.

[Varyon]

Originally Posted by Coinage

Okay, this could be doable, but it would take a bit of work. The GM would have to pay attention as to how much damage is being applied to each character. That could result in a LOT of book-keeping however. Plus, the GM would have to distinguish damage caused by the PDIA from damage caused by other attacks.

Needing to track the Symptoms-causing Injury separate from others is the norm for Symptoms but, yes, it's additional bookkeeping.

Originally Posted by Coinage

I do like the idea of treat any ability that doesn't require a roll as normally being a 20- to activate. For every point of damage caused by the PDIA, lower that number. So, if the PDIA causes 4 damage, it now requires a effective skill roll of below 16 to activate.

My own inclination is to just say: Whenever the PDIA causes a certain amount of damage, the victim lowers the same number on the roll to succeed in the roll.

An option here could be to have the penalty using Side Effect rather than Symptoms, setting the level to match with the average damage for the attack (so a 1d attack has the Side Effect priced for -3.5 to the ability). You'd then apply Cumulative +400%. Of course, that's a bit of a problematic price here - even if we treat each -1 as [-20], +400% is equivalent to an additional -20 to activation (so you'd be better off just making the Side Effect be -16 or so from the start, making it only activated on a Critical Success). Or you can ditch the Cumulative aspect.