spells/abilities that lower SR

[herculesftw]

what spells/abilties lower spell resistance?

[Crake]

not quite lowering spell resistance, but assay spell resistance gives you +10 on the caster level check to overcome a target's spell resistance for 1 round per level, swift action, 4th level spell iirc.

[Karnith]

The spell Lower Spell Resistance (Draconomicon) does exactly what its name suggests.

The spell Subvert Planar Essence (Complete Divine) creates an emanation within which outsiders must save or have their SR and DR reduced by 10.

Taking the feat Undo Resistance lets you lower an opponent's SR when you successfully sneak attack it with a cold iron weapon.

15th-level Spellthieves get the class ability Steal Spell Resistance, which reduces an opponent's SR when you sneak attack them.

[Bakeru]

The MIC has the Shattermantle (+1) property for weapons. Whenever a weapon of this types strikes a creature, it lowers that creature's spell resistance by 2. It only lasts until the beginning of your next turn, but it explicitly stacks, so hand your two weapon fighter two of these and let him loose. The more he hits, the more the mages hit.

[Arc_knight25]

I know its not what your looking for and its probably the most obvious thing to do. But just take Spell penetration and greater spell penetration for a total of +4 to your caster lvl check. If this is Pathfinder be an elf to gain an additional +2.