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 10 TP or more, you may spend all TP to deliver two special light blade attacks (at half your STR or DEX modifier if you use DEX 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 20 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+ half of your character level + your Dexterity modifier) or be sapped for 3d4 rounds that deals 6d4 points of non-elemental damage.