When something calls for your reach and you have multiple things with different reach values, what is actually your reach?
The plant eidolon made me ponder on this. Its ability growing vines says
All your eidolon's melee unarmed attacks gain the reach trait.
Its other ability field of roots says
All enemies within your eidolon's reach take damage of the same type and amount as your eidolon's most damaging Strike, depending on their Reflex saves.
When field of roots is referring to the eidolon's reach, is there a difference between the eidolon's reach and the eidolon's reach with it's melee unarmed attacks? Hypothetically, if eidolons could use weapons, would that also be a separate instance of its reach, or is it all interchangeable when something asks for your reach?
This has been a question ever since Monk wanted to take Monastic Weaponry, grab a Bo Staff (that has reach), and use that to increase the radius of Tangled Forest Stance imposing the immobilized condition.
Ah, I'm glad it's known. I haven't played an overly reach-based character yet so I've managed to avoid all of this.
Yup. Definitely known.
It's not answered. But it is known.
IMO the Bo Staff/Tangled Forest question has an easy answer, as does Field of Roots (though it's less straightforward it still involves an attack, which in this case does have range). Paizo often skips answering questions like this, I think to discourage being judges between rules lawyers and to encourage tables tuning their own games' rigor & flexibility.
That said, there's PFS, where I'd have to wing it re: whether a creature's regular "grab, interact, etc." reach also increases to match any/some unarmed attack's reach. Or maybe the forms of so many attacks defies having a blanket rule, with which I'm okay and guess have to default to.