A couple of combo's I've been using with my sorcerer:
Empowered Ray of Enfeeblement + Web = most creatures are rendered incapable (or nearly so) of movement.
Follow it up with a Fireball, their reflex saves are at a -2 due to being entangled, and they take an extra +2d4 fire damage (no save) from the burning webs.
If you have more time (or multiple targets), toss a Slow into the mix, with reduces their Reflex saves against the Web, and then they will have a -3 on their save against the fireball.
Empowered Ray of Enfeeblement + Web = most creatures are rendered incapable (or nearly so) of movement.
Follow it up with a Fireball, their reflex saves are at a -2 due to being entangled, and they take an extra +2d4 fire damage (no save) from the burning webs.
If you have more time (or multiple targets), toss a Slow into the mix, with reduces their Reflex saves against the Web, and then they will have a -3 on their save against the fireball.