2 archetype question

[neferphras]

Let me start by saying i know the RAW answer to the following question. I am posting to see if the current RAW answer makes sense, or should be modified, for the situation described.

So RAW states, you can apply the 2 archetypes to a given character as long as they do not modify the same ability. On the surface that makes sense.

I am trying to build well... Gambit i Pathfinder form. And i had until recently been a little frustrated. Using the Harrow Handbook you have the Card Caster Magus... COOL what a great start. Gets me most everything thing i was thinking of. The problem i had in the Magus build Charisma is the natural tank stat and well i dont really want to tank charisma on a charming roguish character.

Then i bought Advanced Class Guide and i see the Eldritch Scion, a charisma based Magus.. and for a moment i thought all my dreams were answered. Magus has a number of archetype combos that can be done. Alas both Card Caster and Eldritch Scion modify Arcane Pool.

That bring me to my question, because they modify arcane pool in entirely different, and not conflicting ways.

Arcane pool has 2 parts.
1. Gives you the ability to enhance your weapon with a pool of energy (int based)
2. Lets you add specific bonus to your weapon, typically for melee.

Eldritch Scion modifies number one, changing the power to charisma based.

Card Caster changes number 2. giving the character a different set of bonus to add to their ranged weapon.

Is the same ability modified, yes for sure it is. Are the modifications in conflict, absolutely not, not even slightly. So the question i have out there is this: There are a number of powers that various classes have that have many parts. Arcane Pool is really just one of a few examples, was the ruling made with that in mind? or.. was it intended to only apply to a given part of ability when it has many parts.

Thanks for your thoughts in advance

[blahpers]

These sorts of questions are as old as archetypes themselves. The ruling was made with that in mind--and also with the understanding that a particular GM can waive that restriction. The alternative leaves the rules for combining archetypes undefined since there would be no hard-and-fast method to determine whether or not an overlap was okay.

[Diekssus]

I would tend to go with the idea that because a GM can overrule anything in a game, It is fine for the rules to be the way they are. And while that is from a practical sense. From roleplaying a respective it also makes a lot of sense, because of the way that the archetypes are written up.

So yeah I'm going with the rules are fine.

[Iron Giant]

If the archetype ability says "this ability replaces X" or "this ability replaces X" then it doesn't work with another archetype that also replaces or modifies X. If this is explicitly stated, then there is no question of the legality. Sometimes (often with bonus feats, class skills, and weapon proficiency) this is implicitly stated, but it shouldn't be hard to discern.

For instance, a lot of people would like to be able to take a one level dip in Sohei/Master of Many Styles to get a style feat and the Sohei surprise round ability, but one adds an option for a bonus feat and the other changes the bonus feats. Mechanically someone could easily just choose not to take the extra bonus feat option, but it is still an illegal combo.

I think it's worth keeping in mind that sometimes the designers purposely don't want to see certain archetype combos together for a variety of reasons. While there might not be a reason the two couldn't work together, that's their way of restricting access to both. As stated before, a GM in a home game could obviously rule the way they want, but in an environment like PFS you'll have issues.