Wrathful Castigation

You brandish the whip, and your target begins to shake uncontrollably, then collapses on the ground, its spasms eventually fading as it dies.

(Spell Compendium, p. 243)
Originally posted on D&D tools

Enchantment (Compulsion) [Mind-Affecting]

Level: Sorcerer, Wizard 8,
Components: V, S, AF,
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Target: One living creature
Duration: 1 round/level (D)
Saving Throw: See text
Spell Resistance: Yes

This spell causes wracking pain and violent convulsions, ending in death. The target creature must make a Will save or writhe in pain, helpless, before it dies 1 round later at the start of your turn. A creature that makes the Will save must also succeed on a second Will save or be dazed and take a -4 penalty on saving throws for the duration of the spell.

Focus: A whip.