I'm having a go at designing some new feats for an Eberron game I'm intending to run.
I thought I'd share them on here to get some feedback and also invite anyone who wanted to to share any Eberron specific feats, spells, class features etc that they've invented.
Anyway, here we go:
Child of Winter Feat:
PLAGUEBRINGER [GENERAL]
Prerequisites: Wis 13, Child of Winter, Knowledge (nature) 4 ranks, any neutral, nongood alignment (N, LN, N, CN, or NE), able to cast Breath of the Jungle.
Benefit: You can “lose” a prepared spell in order to cast any spell from the list below of the same level or lower.
You may use this ability a total number of times per day equal to your Wisdom modifier.
1. Breath of the Jungle: Fog makes poison and diseases harder to resist.
2. Decomposition: Wounds deal 3 extra points of damage each round.
3. Infestation of Maggots: Touch attack deals d4 Con damage/round.
4. Contagious Touch: You infect one creature/round with chosen disease.
5. Mass Contagion: As contagion, but 20-ft. radius.
6. Pox: One creature/level takes 1d4 Con drain
7. Scourge: Inflicts a disease that must be magically cured, one subject/level.
8. Befoul: Large amount of water becomes poisonous.
9. Despoil: Kills plants, damages objects in 100-ft. radius/level.
The spells all come from the spell compendium, book of vile darkness or Lords of Madness. It is inspired by the Spontaneous affliction alternate class feature in Exemplars of Evil and the Spontaneous Healer/Summoner/Wounder feats in Complete Divine.
I felt it fit thematically with the Children of winter as plaguespreaders.
Is it too powerful?
As I'm not a DM myself, I'm not really qualified to pass judgement on the power level of your Plaguebringer feat.
Here, however, is a feat in the same vein as Practiced Spellcaster (Complete Arcane pg. 82/Complete Divine pg. 82) that would be of benefit to artificers (particularly multiclass artificers):
PRACTICED ARTIFICE
Your infusions are more powerful.
Prerequisite: Spellcraft 4 ranks, Use Magic Device 4 ranks, at least one level of artificer (Eberron Campaign Setting pg. 29).
Benefit: Your caster level increases by 4. This benefit can’t increase your caster level to higher than your Hit Dice (or your Hit Dice +2, in the case of meeting caster level prerequisites for creating magic items). However, even if you can’t benefit from the full bonus immediately, if you later gain Hit Dice in levels of classes other than artificer (including other magic-using classes such as cleric or sorcerer), you might be able to apply the rest of the bonus.
For example, a human 5th-level artificer/3rd-level rogue who selects this feat would increase his caster level from 5th to 8th (since he already has 8 Hit Dice). If he later gained another level of rogue, he would gain the remainder of the bonus and his artificer caster level would become 9th (since he now has 9 Hit Dice).
This feat does not affect your infusions per day or infusions known. It increases your artificer caster level only, which would help you increase the duration and other effects of your infusions.