Damage Reduction vs magical slashing damage.

[Ben Williams]

When a spell-like ability causes a hampering effect that can be ignored by taking "magical slashing damage", does that damage bypass DR?

[Claxon]

Well knowing the spell in question would probably help understand the greater context but taken at face value...

No. Magical slashing damage is still physical damage that would be reduced by DR, unless the DR was some sort that was bypassed by magical damage. For something kind of similar incorporeal creatures take no damage from non-magical physical damage and take only 50% of magical physical damage.

Regardless, a creature with DR might have no idea whether it would work or not but might be inclined to try anyways, assuming they're generally protected. Or they might think the damage is small enough that accepting the damage is better than accepting the other effect.

[Ben Williams]

The specific ability is the Bindings of the Obliged from City of Seven Seraphs book, its a force descriptor veil(spell-like). It reduces movement, the movement reduction can be ignored by taking the "magic slashing damage" which specifically calls out that it affects incorporeal because its a force effect.

[Derklord]

"if a magical attack specifically mentions that it deals bludgeoning, piercing, or slashing damage, DR affects that damage normally, as if it were from a physical weapon."

[Claxon]

I didn't have that fancy FAQ, but it seems my response is correct. It can be mitigated by DR (as long as the DR isn't bypassed by slashing damage).

[Diego Rossi]

This item?

That item will be affected by the creature DR, if the DR stops magical or slashing damage.

Converting a form of damage into another can work differently, depending on the specific text of the ability that delivers the damage and of the ability that changes the damage, but the basic rule is the one Darklord cited.

[Pizza Lord]

In the case of bindings of the obliged, the damage that affected enemies take will be reduced by Damage Reduction (unless it's bypassed by magic or by slashing). So a skeleton (DR 5/bludgeoning) which chooses to tear the chains free on the start of its action will take 5 less damage from the 3–18 magical slashing damage that the spell causes. It will then be unaffected by the movement restrictions of the spell whether it took any damage or not.

This is equivalent to the effects of an ice storm spell, which deals 3d6 bludgeoning damage and 2d6 cold damage. The bludgeoning damage would be reduced by DR, but the cold damage would not be (that would be reduced by energy resistance).