I really like the spell Cometfall from SpC. It ignores SR, and does damage equivalent to a fireball. Creature that fail their reflex are knocked prone as well.

The only problem is that you must have adequate room above the target to cast the spell, so it will not be great in caves or dungeons. Outside it's good though.

Because the comet is conjured above the creature, they don't get to pinpoint your location.