Abilities: Special, Extraordinary, Spell Like, Supernatural, Natural, get 'em here.

[Arcanist]

Is Bardic Music is an Extraordinary ability? It neither provokes an attack of opportunity and is unlabeled so where does it default? Is it a Natural ability?

Better yet, how about Bardic Knowledge? Same circumstances? A Commoner taking their next level as a Bard spontaneously suffers a physical mutation that lets them sing and "knows some relevant information about local notable people, legendary items, or noteworthy places"? This is starting to sound like the plot for Heroes where everyone just spontaneously starts to develop super powers

For the record, I have no problem with FAQ as a rules source. But the FAQ clearly states that only non-magical unlabeled special abilities should be Ex. Whatever else you think spellcasting is, attempting to argue that it's non-magical is a dead end.

If Spellcasting should be considered a "magical unlabeled" special ability (A Supernatural ability I suppose?), than Anti-magic field blocks the "Spells" class feature instead of the actual spells. Invoke Magic and Initiate of Mystra stop being things...