Extra Attack Stacking

[scon]

Hey all.

I'm sure there's a straightforward answer to this question, and I suspect I already know.

Frenzy grants an extra attack, and states that it does not stack with other effects such as Haste.

What exactly falls under "effects"? Would extra attacks due to feats such as Lightning Fists (Sword and Fist) or Snap Kick (ToB) stack with Frenzy, or not?

Thanks

[Biffoniacus_Furiou]

Frenzy doesn't stack with Haste or other effects which also don't stack with Haste, such as the Speed weapon property or Righteous Wrath of the Faithful.

However, effects which grant an extra attack that do not say that they don't stack with Haste should stack with Frenzy just fine. An extra attack that's triggered on a specific condition, such as Snap Kick, or an extra attack for which a cost is paid, such as Flurry of Blows or Rapid Shot, will typically stack with Haste and thus should also stack with Frenzy.

[FMArthur]

The ones that don't stack all mention it. In fact they usually (or always?) use the one from Haste as their example. Snap Kick stacks.

3.0 things, I don't know; without the Haste example (Haste worked differently), maybe they just didn't mention it? Maybe it was a restriction introduced to combat a 3.0 problem?

[scon]

Thanks guys.

So let's see if I'm understanding correctly.

Let's call "A" the group of effects that state "This does not stack with other extra attacks such as from Haste".

Similarly, "B" will be the group that doesn't state a restriction.

So then, things in A will not stack with each other, but they will stack just fine with things from B?

Obviously things from B will stack with each other.

[Douglas]

The way I've always interpreted it goes like this:
There are two categories of effects that give bonus attacks - "Haste-like" and "Not Haste-like". Haste-like effects typically have no drawback or penalty, last at least as long as a typical single encounter, and either don't take an action to activate or only need to be activated once per encounter. Non Haste-like effects typically come with a drawback or penalty that makes it a trade-off (Rapid Shot), only last one round (Dancing Mongoose), require repeated activation or maintenance of the effect, or have some other kind of limitation.

The traits in the previous paragraph are only typical generalities, however, not defining rules. They only serve to help understand why each effect is in the category that it is. The factor that actually definitively determines which category an effect is in is this: every Haste-like effect, without exception, specifies that it does not stack with Haste or similar effects; every non Haste-like effect lacks such a clause.

You can benefit from the extra attack(s) of only 1 Haste-like effect at a time. Any number of non Haste-like effects can stack bonus attacks without limit, however, and all of them also stack with a single Haste-like effect. Attempting to stack a large number of non Haste-like effects can work, but will quickly accumulate a big pile of penalties, costs, and other limitations that make it less effective than the optimizer might have hoped.

So, pretty much, you got it right, I just added some explanation for why it works this way.