Nurglitch

Nurglitch and Bilios are subject to Frenzy and Hatred. Such is the inspirational effect Nurglitch has on his army that no Clan Pestilens units will lose their Frenzy whilst Nurglitch is still alive.

Any non-Clan Pestilens unit with a model within 6" of Nurglitch is at -1 WS. Furthermore, any such model in base contact with Nurglitch at the end of any close combat phase automatically takes a S 4 hit which Ignores Armour saves, that counts towards combat resolution.

The Plague Lord has Ward Save (5+). In addition, neither Nurglitch nor any unit he joins will ever suffer wounds from spells cast from the Lore of Plague or Lore of Nurgle. Furthermore, they automatically pass the test for the effects of plague censers.

Units with this rule add what would be their Combat Resolution bonus from ranks to their LD value for any Psychology and Break tests. To calculate the LD of a unit with the Strength in Numbers rule, first determine the unit's LD as normal and then add the rank bonus of the unit to this value, up to a maximum LD of 10. 

Note that a Skaven General confers his basic LD and then units modify it with their own rank bonus. Any bonus from the ranks of the General's unit is not passed on to units within his Inspiring Presence range.

If for any reason a Skaven unit loses its rank bonus, it also loses its LD bonus. For instance, fleeing units do not have a rank bonus, so fleeing Skaven must use their basic LD.

All models in the Skaven army have Swiftstride when fleeing.

Models that cause Terror also cause Fear. In addition,
the following rules apply. Fear-causing models or
models with Immunity (Fear) treat Terror-causing
monsters as causing Fear, rather than Terror – this is an
exception to the rule that makes Fear-causing creatures
immune to Fear. Terror-causing models have the
Immunity (Fear/Terror) special rule.

Run for Your Lives!
If a Terror-causing creature declares a charge, the target unit must immediately take a Panic test. If the test is passed, all is well and the unit can declare charge reactions normally. If the test is failed, the unit must make a Flee! charge reaction. Note that, if the target unit is not allowed to take any charge reaction (if, for example, the Terror-causing unit charged as a result of a pursuit or a random move), then the target does not take this test.

If a unit wishes to declare a charge against an enemy that causes Terror, it must take a Psychology test to overcome its terror first. If the test is failed, it may not declare the charge against the Terror-causing unit, but may choose to declare a charge against another unit following the rules for Redirecting a Charge. If the Psychology test is passed, the unit may declare the charge as normal.

Units belonging to each of the Greater Clans (Pestilens, Eshin, Moulder, Skryre) may only be joined by characters from the same Clan.