Mortarion

Just after an enemy unit ends a Normal, Advance or Fall Back move within 9" of a friendly DEATH GUARD unit that is within 6" of this model, if that DEATH GUARD unit is not within Engagement Range of one or more enemy units, it can make a Normal move of up to 5".

In your opponent’s Shooting phase, when a friendly DEATH GUARD unit within 6" of this model is selected as the target of an attack, this model can use this ability. If it does, after the attacking unit has finished making its attacks, that DEATH GUARD unit can shoot as if it were your Shooting phase, but when resolving those attacks it can only target that enemy unit (and only if it is an eligible target).

In the Fight phase, when a friendly DEATH GUARD unit within 6" of this model is selected as the target of an attack, this model can use this ability. If it does, until the end of the phase, each time a model in that DEATH GUARD unit is destroyed by a melee attack, if that model has not fought this phase, roll one D6. On a 2+, do not remove it from play; that destroyed model can fight after the attacking unit has finished making its attacks, and it is then removed from play.