Relative Power of Su vs. Ex Abilities

[Tvtyrant]

As a general rule, getting the same ability as an extraordinary ability rather than a supernatural ability is better. My question is, how much better?

The two abilities I am most interested in are Wildshape and Summon Nature's Ally. Assuming they remain identical otherwise, how much more valuable would they be as Ex then as Su's?

[QuickLyRaiNbow]

Hugely more valuable. Being able to retain your primary trick - summoning ability for a summon-focused Druid or Wildshaping for someone dedicated to melee combat - while within an AMF would be huge. One of the only ways to deal with a regular caster - not one that's optimized to the 9s sporting Initiate of Mystra or insane Craft Contingent Spell options - is to get them within an AMF. With those as Ex options, you can shrug, turn into an Elder Air Elemental and wreck face with your perfect flight speed or dump Greenbound summons on your opponent.

[Fouredged Sword]

In high op or high level, very good.

In mid/low op play or lower levels you will see less returns.

[Tvtyrant]

Let's say that these are differently named abilities, and so are other than their Ex form strictly vanilla(no greenbound, augmented, or pseudo-natural summons, no aberration shape, etc.)

[QuickLyRaiNbow]

So your SNA is basically a SLA that's Ex in nature? No summoning feats apply to it? If that's the case, it's going to depend on more information (but will generally be worse). If it acts in all ways as the spell, with components and so forth, then it's really only valuable in an AMF situation. If it can be used without any verbal or somatic components, then it's still very useful as a utility feature and a get-out-of-jail-bruised-but-not-dead card.

Outside of AMF situations, there's not really much difference between an Ex ability and a Su ability. So the usefulness is going to depend almost wholly on how often you encounter those.

[Curmudgeon]

Outside of AMF situations, there's not really much difference between an Ex ability and a Su ability. So the usefulness is going to depend almost wholly on how often you encounter those.
There's one big difference.
Using an extraordinary ability is usually not an action because most extraordinary abilities automatically happen in a reactive fashion.
Using a supernatural ability is a standard action unless noted otherwise.

[QuickLyRaiNbow]

True, though Wild Shape is specifically one standard action and SNA has a cast time. If those would change to free/immediate actions, then it's potentially encounter-breaking in the case of SNA and more powerful for Wild Shape. But there aren't a lot of active-use Ex abilities; every one I'm aware of triggers automatically. Since it doesn't say they'd become free actions I have to assume they'd be treated as default.

[NichG]

Since there isn't really any precedent for converting an ability from supernatural to extraordinary, 'usually' doesn't really mean much here unfortunately. If it was 'always' that'd be another story...

Can an Ex ability be counterspelled or dispelled?

[Tvtyrant]

I believe that would be a no.

The actual reason I am asking is I want to make a class where the character is made of nanites, which "wildshapes" by taking other creatures forms and "summons" things by making nanite copies.

[TuggyNE]

Can an Ex ability be counterspelled or dispelled?

Neither Ex or Su can be counterspelled or dispelled, or even disjoined. The differences between them have already been largely detailed, though.