You blend shadow into your spells, increasing their efficacy at the price of susceptibility to light.
Benefit: When you cast a tenebrous spell in darkness or dim light, the spell’s effective caster level and any associated save DCs are increased by 1. Any attempts at dispelling a tenebrous spell in darkness or dim light take a –2 penalty on the dispel check.
Casting a tenebrous spell in bright light is difficult, and requires a concentration check (DC 15 + twice the tenebrous spell’s effective spell level). Attempts to dispel a tenebrous spell in bright light gain a +4 bonus on the dispel check.
You cannot use this feat on spells with the light descriptor. A tenebrous spell uses up a spell Slot one level higher than the spell’s actual level, except in the case of spells with the darkness or shadow descriptor or of the illusion (shadow) subschool; this feat does not change the effective level of those spells (but still counts as using a metamagic feat for all other purposes).
Targets of your darkness spells radiate darkness.
Prerequisite: Tenebrous Spell.
Benefit: An umbral spell gains the darkness descriptor. As long as the spell is in effect, the creature or object affected radiates darkness in a 10-foot radius, reducing illumination similar to the effects of the darkness spell. Nonmagical sources of light, such as torches or lanterns, do not increase the light level in this area. Magical light sources only increase the light level in an area affected by an umbral spell if they are of a higher level than the umbral spell’s unmodified spell level. This effect does not stack with itself or with any other effect that creates darkness.
Level Increase: +2 (an umbral spell uses up a spell slot two levels higher than the spell’s actual level.)
You cannot use this feat on a spell with an instantaneous duration or a spell that does not target a creature or object.
you have to take all the penalties, but an umbral spell gains the darkness descriptor, so qualifies for the tenebrous extra. So it would be +1 level, hard to cast in bright light, easier to dispel in bright light.
I count +2 for Umbral, +0 for Tenebrous?