Fair enough. Thanks for taking the time to answer my questions.

Just tried a bit the Alter Self spell on a sorcerer. I think it more or less works the same, with respect to appearance and feats gained from the target shape. The big difference, as far as I can see, is that the Alter Self spell actually has a 'Learn Shape' part (and no way to revert to original shape if you haven't already stored it), whereas the Dragonfire adept's humanoid shape will only assume the form and won't store it upon casting the invocation (and has a 'Return to True Shape' or something like that). Also, with Alter Self I had trouble assuming high level forms (though still lower than mine), while humanoid shape shows no problem as long as the target is the same or lower level I think (possibly even a few levels above mine, though I doubt that). From what I can tell, both 'spells' share the same options dialogue 'Shifter Options', but only with Alter Shape you can actually do something there. Humanoid Shape shows no stored shapes, no way to store the current shape, only the true shape, and that's useless since there is already the 'Return to True Shape' in the invocation menu.


PS: I'm starting to think my installation if messed up. Unless there is something I should have done to enable it, the Shifter (PnP) PrC can only be taken as a druid (so far, I have tried to take the class with both a sorcerer with Polymorph Self or Dragonfire Adept with Humanoid Shape, as stated in the class' description). I'll get the pack installed on a clean module, see what happens.