Blasting into more dangerous

[stenver]

So exactly how overpowered would it be to add this to fire based explosive area spells.

If you fail a reflex save, make a fortitude save or be permanently blinded. Also, make balance DC 10 or fall.

And this to other explosive spells.

If you fail a reflex save, make balance DC 10 or fall.

And to balance it out, how many levels higher should these spells be, if any?

[Altair_the_Vexed]

These would not give characters too much trouble at higher levels, but they'd be devastating at lower levels.

I'd call them metamagic variants, and I'd bump the spell level up two for the blinding version, and one for the knock down version.

[stenver]

So basically the blinding knocking fireball could, for example, be called Greater Fireball and be level 5 spell?