Ways to ignore/lower energy resistance?

[Silly Name]

Pretty much as title. I'm brainstorming some character ideas and I was wondering what methods there are to bypass resistance to fire/frost/acid/etc.

Anything is fine: spells, feats, metamagic, items, class features... As long as it works in some form. Preferably stuff that isn't restricted to a specific type of monster or energy, but I guess those are fine as well if there are no other options.

[Fouredged Sword]

The only general way to reduce energy resistance that I know of is Spellthief 3 granting the ability to steal energy resistance. It allows you to forgo 1d6 of sneak attack damage to grant yourself 10 resistance to an energy type your target has and reduce their energy resistance by that amount.

[Crake]

Searing Spell/Piercing cold completely ignore the fire/cold resistance of the spell's targets, and also deals half damage to creatures immune (though piercing cold is weird in that it doesn't work against creatures with the [cold] subtype).

You could in theory homebrew metamagics for the other elements, I personally made "Shocked to the Soul" which is the electricity variant, which a lightning themed player used to damage demons, but otherwise you could just Energy Substitution to either fire or cold, and apply searing spell/piercing cold as you please.

[Saintheart]

Cheesy, but the Merciful weapon quality. Converts all of a weapon's damage (including the energy) to nonlethal, which Energy Resistance doesn't stop. You might knock the monster out rather than obliterate it, but an unconscious and therefore helpless monster is a dead monster one coup de grace later.

[Crake]

Cheesy, but the Merciful weapon quality. Converts all of a weapon's damage (including the energy) to nonlethal, which Energy Resistance doesn't stop. You might knock the monster out rather than obliterate it, but an unconscious and therefore helpless monster is a dead monster one coup de grace later.

Technically nonlethal substitution would achieve the same result for spells too. Nonlethal subsitution even goes as far as making it very clear that the spells no longer deal energy damage and that spells like fireball no longer have a chance to set things on fire because of it.

[Telonius]

Consecrate and Corrupt Spell (both in CDiv) are metamagics that change half the damage into untyped damage. This can help with spell resistance; a Consecrated Fireball would hurt something that's immune or resistant to fire. Lord of the Uttercold (CArc) changes half cold damage into Negative Energy, which can help if the target isn't immune to both.

Dispel Magic, if the resistance came from a spell.

[Troacctid]

Silver Pyromancer and Sanctified One of Kord allow you to turn fire damage into untyped damage.

[Thurbane]

Elven Spell Lore lets you change the energy type of any one selected spell in your spellbook. So you can throw around Cone of Cold Sonic to your hearts content, with no increase of spell level or casting time. Sonic resistance is pretty uncommon. The benefit of this over Energy Substitution is you don't have to select only one energy type - you can select any of the 5 each time you memorize your spells.

A generous reading of the feat would let you go beyond the 5 basic energy types, such as Negative, Force etc.

[Gruftzwerg]

Imho warlock is the way to go here if you want consistent damage against anything.

First, the regular Eldritch Blast has untyped damage and thus ignores most DR & all energy resistances. If you should face enemies with SR, you can switch to acid damage. And, if the DM tries to keep you under control with enemies that have both SR and Acid Resistance, there is still the Hellfire option.

Have a look at my optimized Glaivelock build if you want to see how a Killer Kobold with a STR score of 1 will annihilate anything that comes across its path. (can be played like some kind of lil sith lord xD )