Where do you see summoning hinders our stuff?
The goonhammer review says it. The contagions of nurgle says "if every unit from your army has the <death guard> keyword (excluding unaligned units), this unit gains the following ability:" I think it means nurgle daemons don't have the keyword so when you summon one you lose the contagion.
In goonhammer they said
"Something players definitely need to be aware of is that while I think there are opportunities to build soup armies that combine Death Guard and Chaos Daemons or other flavors of Heretic Astartes, is that, with the rules as they are currently written, summoning will break your army-wide bonus. While it doesn’t break your Detachment special rules, summoning a unit will turn off your Contagions of Nurgle powers. So think carefully before you sit down to draw that summoning circle and bring Epidemius onto the field."
Edited by Putrid Choir, 22 January 2021 - 09:36 AM.