I've been looking into ways to boost my save DCs, and I came across Harmonic Chorus. There seems to be a bit of inconsistency in the description, which makes me think it may be possible to cast it on yourself.
- The "Target" line says that it has to be cast on "One Living Creature", with no special restriction that it has to be cast on someone else.
- The description says that the spell "lets you improve the spellcasting ability of another spellcaster". However, this line sounds a lot more like the text that lets you know basically what the spell does, and not an outright restriction.
- The spell requires concentration, which means that under normal circumstances, you cannot cast another spell while using it. However, with something like Extraordinary Concentration or Sonorous Hum, a caster could be able to cast it on themselves and maintain concentration while being able to cast other spells.
I feel that the intent of the spell is to cast it on another character and use your own actions to buff their spells by concentration. I feel that the text saying that it is used on other spellcasters is a logical implication of the spell requiring concentration, and not an outright ban on casting it on yourself.
Does this interpretation hold water?
Edit: This specifically applies to D&D 3.5, with any Wizards official books allowed.