Judge Dredd: Judgement Day

The necromancer Sabbat raises the dead worldwide and Mega-City Two is among the cities that fall. Dredd's answer is to propose nuking them, and the death toll passes two billion. It is the bleakest proof of how far the Judges will go to call something order. Garth Ennis wrote it across 2000 AD progs 786 to 799 and Megazine volume 2 issues 4 to 9, all gathered in Case Files 17.