damage for metamagic

[DonAdam]

As far as the average D&D game goes, I think that metamagic feats tend to be highly inferior to Item Creation feats. Extend Spell is the only one I've seen used regularly and with an real effectiveness (being able to rope trick and get a whole night's rest at 4th level is awesome, as is having 48 hours of endure elements).

It is thus that I propose the following rule:

In fantasy novels you often have the idea of wizards pushing themselves to use their magic. In this case, I want casters to be able to push themselves to make their spells more potent.

A caster can use any metamagic feat that he does not have spontaneously (I wouldn't even increase the casting time to a full round), but in so doing he takes 1d6 points of damage per level that the metamagic feat would normally raise the spell's level by.

What do you guys think?

Edit: I realized that it should not be subdual damage, and that it should not be able to be healed magically (to prevent abuse with healing spells).

 

[Firzair]

Hi DonAdam,
IMC we use subdual damage, 2 points of damage per level increase. This subdual damage cannot be healed magically, only through rest.
As all our casters are spontanous casting (house ruled, even wizards and clerics) they alsways have the option of using an available higher spell slot without prolonged casting time or to use straining metamagic by taking subdual damage an having the casting time increased to full round. Quicken spell is available even for straining casting but deals 16 points of subdual damage.
I know it gives much more oomph to clerics with high hitpoints but its ok with our campaign.

Greetings
Firzair