Tales are told of warriors who can slay their opponents with but a single strike of a blade that seeks an armour's merest gap. Whether such an attack is wrought by skill or sorcery matters not – the target is just as dead.
Source: Warhammer Armies Project: Unofficial 9th Edition (v2.2)
Killing BlowURL Copied!
If a model with the Killing Blow special rule rolls a 6 to wound, they automatically slay their opponent – regardless of the number of wounds on the victim's profile. Armour saves and Regeneration saves cannot be taken against a Killing Blow. Ward saves may be taken as normal.
Killing Blow is only effective against Infantry, Cavalry and War beasts. Against other troop types, a successful Killing Blow only inflicts one Wound which Ignores Armour Saves and Regeneration.
Note that if a Killing Blow attack wounds automatically, then the Killing Blow special rule does not come into play. Unless otherwise specified, Killing Blow only applies to close combat attacks.
For the purposes of combat resolution, successful Killing Blows score the same amount of Wounds as the slain model had remaining until the point of the Killing Blow was inflicted.