New details from Games Workshop from the Blightwar Box set, starting with the Cycle of Corruption. A continuous effect on the tabletop that cycles through....
via Warhammer Community
https://www.warhammer-community.com/2017/08/28/nurgle-abilities-in-blightwargw-homepage-post-3/
"The Cycle of Corruption represents the shifting tides of Nurgle’s power, as he – and his followers – endlessly cycle between decay and regrowth. At the beginning of the first battle round, the Nurgle player rolls a dice to determine where the Cycle of Corruption begins – from this point on, the cycle moves clockwise every turn, bring new benefits to the Nurgle army or penalties to their enemies:"