Corrosive Spell, Frigid Spell, THUNDERING SPELL

[rferries]

Corrosive Spell [Metamagic]
Your acidic magic gives off toxic fumes.

Prerequisites
Brew Potion, Craft (alchemy) 5 ranks.

Benefits
Whenever you cast a damaging spell with the acid descriptor, any creature damaged by that spell must also make a Fortitude save (save DC 10 + spell level + your relevant ability modifier) or take 1 point of Constitution damage per spell level for each round of exposure. A corrosive spell uses up a spell slot a spell slot of the spell's normal level.

Frigid Spell [Metamagic]
Your ice magic chills creatures to the bone.

Prerequisites
Spell Focus (evocation), Knowledge (nature) 5 ranks.

Benefits
Whenever you cast a damaging spell with the cold descriptor, any creature damaged by that spell must also make a Fortitude save (save DC 10 + spell level + your relevant ability modifier) or take 1 point of Dexterity damage per spell level for each round of exposure. A frigid spell uses up a spell slot a spell slot of the spell's normal level.

Thundering Spell [Metamagic]
Your lightning spells are as loud as thunderbolts.

Prerequisites
Spell Focus (evocation), Knowledge (nature) 5 ranks.

Benefits
Whenever you cast a damaging spell with the electricity descriptor, you may choose to have it deal an additional 1 point of sonic damage per spell level. Any creature damaged by that spell must also make a Fortitude save (save DC 10 + spell level + your relevant ability modifier) or be deafened for 1d4 rounds. A thundering spell uses up a spell slot a spell slot of the spell's normal level.

Other options: Frigid Spell could slow creatures, a negative energy spell metamagic feat that frightens creatures damaged by the negative energy (or gives them negative levels, or deals Con drain)...

[Darth Ultron]

Feats like this can really mess up the game balance.

First ''brew potion'' seems more like a feat tax.

Corrosive Spell seems like a lot of Con damage. With a DC of 15+, targets will fail and take a ton of damage. And then get hit with another acid spell. So maybe ''1 con per spell level'' and it really needs a ''takes up a slot 2 more then the spell level''.

Though ''bad fumes'' does not really feel ''corrosive''.

Frigid Spell a free 1d4 damage to two abilities? And spell focus evocation is a bit odd as a lot of cold spells are not in that school. Such damage should not be so free.

Thundering Spell-woah, 1d8 damage bonus per level is a lot...plus other effects.

They are all just so powerful with just about no costs or balance.

[rferries]

Feats like this can really mess up the game balance.

First ''brew potion'' seems more like a feat tax.

Corrosive Spell seems like a lot of Con damage. With a DC of 15+, targets will fail and take a ton of damage. And then get hit with another acid spell. So maybe ''1 con per spell level'' and it really needs a ''takes up a slot 2 more then the spell level''.

Though ''bad fumes'' does not really feel ''corrosive''.

Frigid Spell a free 1d4 damage to two abilities? And spell focus evocation is a bit odd as a lot of cold spells are not in that school. Such damage should not be so free.

Thundering Spell-woah, 1d8 damage bonus per level is a lot...plus other effects.

They are all just so powerful with just about no costs or balance.

Hey thanks for the reply!

The feat prerequisites are indeed meant to be feat taxes; that plus the limited applicability of the feats (i.e. only certain elements) is meant to balance them out. However I've toned down the Con damage, removed the Str damage, and toned down the sonic damage and removed the stunning.

The toxic fumes connection came from acid pool natural hazards.