Daemons

All the special rules for daemons apply as described in the Warhammer rulebook. In particular note that the Beast of Nurgle has a saving throw of 4+ due to its daemonic intangibility or daemonic aura.

Fear

Beasts of Nurgle are huge and monstrous, and therefore cause fear as described in the Warhammer rulebook.

Attacks

The Beast has D6 attacks from its tentacles, determined during each hand-to-hand combat round. The slime will automatically penetrate the victim's armour, so no armour save is permitted for models struck by the Beast of Nurgle.

Slime Trail

The Beast leaves a slime trail behind it as it moves. This means it is impossible to attack the Beast from the side or rear without touching the slime. Any model attempting to attack the Beast in this way will sustain a single automatic hit as if it had been struck by the Beast itself. This is worked out before the attacker's own blows are struck.