Ambush and Assassinate
100% more Critical Strike Chance against Enemies that are on Full Life
Critical Strikes have Culling Strike
30% increased Damage with Hits against Enemies that are on Low Life
100% more Critical Strike Chance against Enemies that are on Low Life 
Ambush and Assassinate is a notable Ascendancy passive skill for the Assassin that grants more critical strike chance and critical strike multiplier against enemies at full life, and increase damage and more critical strike chance against enemies at low life. It also grants culling strike to critical strikes.