+1 spellcasting classes and spells known

[Venger]

so, for classes with limited spells known lists (sorcerers and the prix fixe classes: beguiler/sorc/dread necro) getting more spells known is a big deal via stuff like sand shaper, wild soul, or fiend blooded.

my question is: if I were to be a sorcerer and qualify for, say, fiend blooded, then go into another class that progressed spellcasting, could I designate fiend-blooded as the class to advance so I could keep advancing its fiendish sorcery, which gives me a new spell known at every even level, or not ?

[Sgt. Cookie]

No, unfortunately not. Since Fiendish Sorcery is a part of the class, you'd have to use Legacy Champion or Uncanny Trickster.

Even then, I don't think you can use an advancement class to advance an advancement class. Lyric Thaumaturge can advance Prestige Bard casting, but that's the only exception.