If I'm a Tiefling who takes the Pass for Human trait, one of the things that changes is my type/subtype: "count as humanoid (human) as well as outsider (native) for all purposes."
Does this mean I could hypothetically take the Defiant Luck feat, which requires me to be human?
Many will say yes, but a few will say no. It is assumed that humanoid (human) entitles you to human feats, but what type/subtype combo entities you to drow racial feats? So the reverse argument hoes that type/subtype is not sufficient for feats etc. Compare this to the similar verbiage for half elf and half orc.
Right, the verbage is half-orcs and half-elves "count as human for all effects related to race" whereas Pass for Human and Mostly Human say they "count as humanoid (human)" for all purposes." For me they amount to the same thing.
In terms of Drow, they seem like a separate race even though they are sort of the same race as elves. I would rule that you'd need a trait or feat such as the half-elf options Drow Heritage or Half-Drow Paragon that explicitly states they count as drow for the purposes of any effect related to race. I'd also allow the cheesy Racial Heritage feat.
J
I tend to be fairly casual on this level of detail, leaning to cool concepts and story potentials, but I wanted to mention the more restrictive counterpoint in the interests fair warning or whatever.
There are some reasons why it strictly RAW wouldn't work, most importantly that the human subtype doesn't even require you to be related to humans (for example creatures that can shapeshift into one get it, too).
However... Pathfinder was written under the design principle of "things should be the same, or they should be different." I don't see a reason the Tiefling racial trait should work differently from the half-orc and half-elf racial traits. In addition, in my spreadsheet of all monsters and NPCs, out of 2099 creatures, I can find exactly one "humanoid (human)" that wouldn't definitely qualify for Defiant Luck, the Deep One Hybrid (monster entry, race entry), and that's probably due to the limited space of the Bestiary entry.
In summary, unless your GM is particularly nasty, it works.
Pathfinder was written under the design principle of "things should be the same, or they should be different."
Ah how great it was when this was the case. Then in 2014-ish SKR left and the writing fell to such a point where the rules writers can't keep track of whether or not Dex to damage abilities are or are not allowed to be increased by 2-handing (slashing grace, agile weapon, UC Rogue finesse training, etc.) and we forget that "magical darkness" is a meaningless term for telling if dark vision can see through Shield of Darkness.
the rules writers can't keep track of whether or not Dex to damage abilities are or are not allowed to be increased by 2-handing (slashing grace, agile weapon, UC Rogue finesse training, etc.)
That is not an example of the design principle being broken, but rather the opposite.
"Things should be the same, or they should be different" doesn't mean you can't have abilities that work differently, it's that divergences from the norm need to be pointed out. And that's what happens, all differences form the norm (which in this case is the default rules, i.e. how you add strength bonus to damage rolls) is explicitly mentioned. Slashing Grace, Fencing Grace, and Dervish Dance say they only work if you one-hand the weapon. Agile calls out that two-handing the weapon doesn't increase the bonus to damage. Starry Grace and unRogue's Finesse Training follow the default rules, which in the former case means a light wepaon can't get higher ability score multiplier from two-handing it, and the latter case does let you profit from two-handing the weapon.
and we forget that "magical darkness" is a meaningless term for telling if dark vision can see through Shield of Darkness.
Writers not following the terminology has happened before SKR's departure, too. Hell, remember Prone Shooter? That was 2011!
Those (prone shooter, monkey lunge, etc.) were genuine mistakes tho and often isolated incidents, not the entirety of a book having these wording problems (a la Blood of Shadows book having many similar issues to the titular Magical Darkness).
I probably should have been more clear with the first example, the X grace feats are in fact mostly fine, and were published in 2014 or shortly there after allowing us to assume SKR's eyes among others had at least touched them before printing. Agile is probably the best example of how to do the wording, even if I don't like them adding these meta-changing weapon abilities in AP splatbooks. However, then we advance ahead a year plus to get UnRogue and Bladed Brush, both being usable with 2 handed weapons and finesse (the latter explicitly being a 2 handed weapon only, the former being able to apply to 2 handed finesse weapons like spiked chain, elven curve blade, etc. for the first time where slashing grace excluded them by nature of being 2 handed) and the fact there isn't an explicit call out one way or the other if you can 1.5 x Dex while 2 handing these weapons is a bit egregious. Hell Bladed Brush is such a mess in so many ways (can you use a shield with it, can you even use slashing grace with it, does said damage get to be 2 handed because you are treated as 1h for the feat but its still actually a 2 handed weapon).
These are just the examples that come to mind, there's plenty more things that are just worded weird that could have been made more precise by just saying "is X but Y" and still be done in fewer words than what we were given.