dnd4
Persistent menace
rogue attack 25

Requirement: wielding a light blade.

Target: one creature

Attack: Dexterity vs. AC

Hit: "2[W] + Dexterity modifier damage, and ongoing 20 damage (save ends)."

Miss: "Half damage, and ongoing 10 damage (save ends)."

Effect: Until the end of the encounter, whenever you deal damage to the target, it takes a -2 penalty to saving throws until the end of your next turn.[MP2:70]

Persistent menace is a daily power available to rogues at 25th level.