Divine Debuffs?

[Bohandas]

Righteous Glare (BoED) causes fear in low HD evil creatures even on a successful will save (and kills them on a failed save) and also causes fear in high hd or non-evil creatures that fail their saves. Inexplicably lacks the [mind-effecting] tag (although the fear effect explicitly duplicates the Fear spell, which does have the mind-affecting tag)

Consecrate Battlefield (HoB) is a wider area, longer lasting, longer range version of Consecrate that also inhibits the creation of undead. It does take 10 minutes to cast though

[i]Subvert Planar Essence(i] (Complete Divine, spell compendium)- reduces damage reduction and SR of outsiders

Vulnerability (SC)- reduces DR

Spark of Life (SC)- Suppresses most of the immunities that come with the undead type (although not their immunity to negative energy or their immunity to effects that only target living creatures)