Blasting Spell (metamagic feat)

[the Jester]

BLASTING SPELL (Metamagic)

You can cast spells that blast enemies from their feet and do extra damage.

Prerequisites: Empower Spell

Benefit: Any spell that deals force, positive or negative energy, or any type of elemental energy damage can be affected by this feat. A blasting spell’s damage die type is increased by one (1 point to 1d2 to 1d3 to 1d4 to 1d6 to 1d8 to 1d10 to 1d12 to 2d8) and, if there is a cap on the number of dice of damage that the spell deals, it increases by five (if based on caster level) or two (if based on half caster level). A blasting spell that deals energy or force damage but normally can only target creatures can target objects as well. In addition, any creature that fails its save against the blasting spell is knocked prone. (If a blasting spell does not offer a save, a Reflex save is allowed to avoid being knocked prone.) Finally, a blasting spell ignores objects’ hardness.

***

What should the level increase on this be? What if I changed one little thing and allowed blasting spells to ignore only half of an object's hardness? Let's look at some examples.

Ex. 1: Magic missile.

A blasting magic missile deals 1d6+1 points of damage per missile. A target hit must make a Ref save or be knocked prone. It can tartget objects and ignores hardness.

Ex. 2: Fireball.

A blasting fireball deals up to 15d8 points of fire damage. All creatures caught in the area that fail their saving throws are knocked prone. This spell is hell on objects, too.

Ex. 3: Polar Ray.

A blasting polar ray deals up to 30d8 points of cold damage. A creature hit must make a Ref save or be knocked prone. The ray can shatter most objects handily.


Opinions?

 

[Xath]

There's a similar feat to this out there that knocks opponents prone at the edge of the spell range, but it doesn't do the extra damage thing...

:goes to look it up:

 

[Xath]

It's called Explosive Spell, and it's in the Complete Arcane. It blasts the creature to the edge of the spell's radius on a failed save, they're knocked prone, and they take an additional 1d6 damage for every 10 feet moved. It takes a spell slot 2 levels higher than normal.

 

[Machiavelli]

I found the Explosive Spell metamagic for my Geomancer and (as promptly as I could) squeezed in Widen Spell and Divine Metamagic. Now a few of his fireballs have a radius of 40 feet and do up to 10d6 fire + 4d6 bludgeoning, knocking opponents prone quite far away from me (or next to the barbarian in my party if I plan it right, so that he can make sure it's dead!)

The unique feature of Blasting Spell is not the extra damage, which makes for some seriously wicked damage but can be eclipsed by Empower (+2 lvls) or utterly dwarfed by Maximize (+3 lvls). The unique idea is ignoring objects' hardness, which with the little extra damage (like half of Empower, so +1 lvl) would make a Blasting spell mostly on par with much higher-level sonic spells. Sonic spells generally do one hit die LESS damage, so Blast Spell is even more like a combination of Empower and Energy Admixture[sonic] (which doesn't actually exist, but would probably follow the trend of reducing the sonic damage die if it did; +0 lvls, by the way) You've already included Empower as a prerequesite, so you're not giving out a 2-for-1 deal on feats. In that light, I'd give it a +2 spell level, just like Empower.
However, you're also knocking enemies prone. Add another level for that: +3 lvls.

 

[Pssthpok]

I'd say +3. A: It's better than Empower (+2), but the fireball example doesn't compete with a delayed blast fireball (7th), so a +3 should suffice.