Once you find a target’s weak point, you can easily strike it again.
Prerequisite: Sneak attack +5d6.
Benefit: If your sneak attack hits, your first attack against that creature on your next turn is also considered a sneak attack even if it wouldn’t normally qualify.
Using this feat reduces your first sneak attack’s damage by 4d6. The resulting second sneak attack deals its full extra damage.
Source: Complete Scoundrel, page 80.