A Plagueburst Mortar is the primary weapon of the Plagueburst Crawler, a Daemon Engine that provides mobile artillery support to the Death Guard Traitor Legion. Their fearsome Plagueburst Mortars boast a parabolic fire arc and terrifying range, while the shells they fire combine high-radius explosives with lethal clouds of corrosive daemonic spores to inflict damage comparable to that of Imperial Demolisher Cannons. The drawback of this weapon is its inability to fire at targets that are closer than its minimum range. Shell after shell whistles down to explode amidst the enemy ranks. Every shot spreads billowing clouds of lethal spores amidst shock waves of fire and shrapnel.
An area under sustained bombardment from these weapons becomes so saturated with foul spore clouds that it is inimical to all life. Armour provides scant protection, for the daemonic spores chew through ventilator grills and enviro-seals, corrode the thickest adamantium plating, and wear through rockcrete layer by layer until they spill into even the deepest and most well-protected bunkers. These hideous effects have made the Plagueburst Crawler a much-hated weapon of war. Enemies strive to destroy them at any cost, while even the daemons of Nurgle look at them askance. After all, where the Plagueburst Crawlers strike, there can be no cycle of rebirth, no matter how foul. For its victims, there is only ever-lasting death.
- Codex Heretic Astartes - Death Guard (8th Edition), pp. 51, 64, 86