You can deliver a pair of special light blade attacks that causes a foe to be inflicted with twin viper bites.
Prerequisite(s): Shadowstitch, BAB +9.
BENEFIT
At 5 TP or more, you may spend all TP to deliver two special light blade attacks (at half your Strength or Dexterity modifier if you use Dexterity for damage) that takes a place of an attack of a full-attack or just a single attack. These attacks deal damage as normal and cause the target to make a Fortitude save (DC 10 + half of your character level + your Dexterity modifier) or be sapped for 1d4 rounds that deals 2d4 points of non-elemental damage. At 10 TP or more, you may spend all TP to cause the target to make a Fortitude save (DC 12 + half of your character level + your Dexterity modifier) or be sapped for 2d4 rounds that deals 4d4 points of non-elemental damage. At 15 TP, you may spend all TP to cause the target to make a Fortitude save (DC 14 + half of your character level + your Dexterity modifier) or be sapped for 3d4 rounds that deals 6d4 points of non-elemental damage.