Need help to understand Corrosion power (M&M 2nd edition)

[Walking Dad]

Hi,

as I understand, the Corrosion power is Strike linked with Drain (Toughness).

The Corrosion description says it removes one toughness rank / power rank.

If a character has Force Field 3 (continous, ablative), Protection (impervious extra) 3 and a Con mod of 3, his Toughness save looks like:

Toughness 9 / 6 (without Force Field)*
*3 Impervious

How will it look like being hit by a Corrosion 4 attack?

Which type of toughness is drained first?

 

[Piratecat]

That's a great question. The way corrosion works is that the character would (in this case) make a DC 14 fortitude save.

If he makes it, he loses no toughness and then makes a DC 19 toughness save against the corrosion's normal damage.

If he fails the initial DC 14 fortitude save, 4 points are subtracted from the save bonus. It doesn't remove them. That means that the player's following toughness saves (including the DC 19 one against the corruption damage) would be normal, including Impervious, but reduced by 5. Repeated use can bring a toughness save as low as -5!

Honestly, though, once the save got below 0 I'd toss the player a hero point and tell him his imperviousness was gone. That seems fair.

 

[Walking Dad]

Thanks.

Another related question:

The Drain description says it drains 1 Power Point of the trait each round. Is Impervious Toughness worth 2pp/level in this regard? Would it only be reduced by half the Drain rank?

 

[Victim]

Thanks.

Another related question:

The Drain description says it drains 1 Power Point of the trait each round. Is Impervious Toughness worth 2pp/level in this regard? Would it only be reduced by half the Drain rank?

Yeah, a Drain removing 4 power points of toughness would reduce impervious toughness by 2 ranks.

 

[Piratecat]

Yup, makes sense to me.

Dang it, now I want to make an entropy-based hero with corrosion.

 

[ValhallaGH]

What P-Cat's initial response leaves out is that Corrosion (and Disintegrate) explicitly treat Impervious Protection / Force Field as counting twice.

So treating Impervious as 2pp is not a house rule, it's the rules as written.

Have fun.

 

[Piratecat]

Yuppers, I missed that. Good catch. Much better than my "eh, your impervious is gone" handwave.

 

[Walking Dad]

What P-Cat's initial response leaves out is that Corrosion (and Disintegrate) explicitly treat Impervious Protection / Force Field as counting twice.

So treating Impervious as 2pp is not a house rule, it's the rules as written.

Have fun.

Really? Where?

CORROSION
Effect: Damage, Drain, Affects Objects
Action: Standard (active)
Range: Touch
Duration: Instant
Saving Throw: Fortitude/Toughness
Cost: 3 points per rank

Your touch causes matter to weaken and corrode. Living targets
make a Fortitude save. If the save fails, subtract the amount
of the failure from the target’s Toughness save bonus, up to a
maximum of your power rank, before inflicting damage equal to
your power rank. Nonliving objects lose Toughness equal to your
rank automatically and suffer damage according to their lowered
Toughness score. Damage is inflicted whether the target loses
Toughness or not. A living target’s Toughness save cannot drop
below –5, an object’s can drop to as low as –10. Living targets
recover lost Toughness at a rate of 1 point per round. Objects
must be repaired.

POWER FEATS
• Reversible: You can remove and repair damage caused by
your Corrosion power at will as a free action.
EXTRAS
• Area: An Area Corrosion effect automatically affects everything
in the area around you. This can be problematic, to say
the least, when it comes to things like floors, walls, ceilings,
and even the ground! To be most effective, you should apply
the Selective Attack modifier to an Area Corrosion effect.
• Range: A ranged version of Corrosion is the Disintegration
power

 

[ValhallaGH]

Huh. You must be using Ultimate Power for your power entries.

M&M 2e FAQ (page 5)
Is Impervious Toughness more effective against Corrosion and Disintegrate?
Yes. Those powers reduce Impervious Toughness by half the usual amount (half the power’s rank, rounded down, rather than the power’s full rank).

 

[Walking Dad]

Thanks!

Downloading it now.