Do not make a wound roll or saving throw (including invulnerable saves) against a mortal wound – just allocate it as you would any other attack and inflict damage to a model in the target unit.

Each mortal wound inflicts 1 point of damage on the target unit, and they are always applied one at a time.

Some attacks inflict mortal wounds – these are so powerful that no armour or force field can withstand their fury. Note, that while similar in many regards to Aura abilities, Contagion abilities are not affected by abilities that affect Aura abilities, and vice-versa.

if an enemy unit is within range of two models with the same Contagion ability, that Contagion ability only applies to the enemy unit once). The effects of multiple, identically named Contagion abilities is not cumulative (i.e. Contagion Abilities Contagion abilities affect enemy models or units within Contagion Range - this changes with the battle round number, increasing as the battle progresses, as shown in the table below. Such is its malefic nature, they can even undo metallic bonds, alien psychic materials and all manner of other elements and components, rendering even armoured vehicles vulnerable.If every unit from your army has the DEATH GUARD keyword (excluding UNALIGNED units), this unit gains the following ability: Nurgle’s Gift (Contagion): While an enemy unit is within Contagion Range of this unit (see below), subtract 1 from the Toughness characteristic of models in that enemy unit. Whenever they march to war, these diseases spread, contaminating all around, sapping the strength of its victims, draining them of energy, withering their muscles and overwhelming their immune system. The Death Guard are carriers of countless infections and contagions, each a gift from Nurgle.

Chaos sicaran battle tank