Just finished this mission on Heresy, supposedly with no modifiers:
It was a real slog. Proof in hand:
It’s not like we took our sweet time ; normally, a normal Heresy mission takes me between 25 and 30 minutes.
But this time, enemies just trickled in NON-STOP. It wasn’t a full horde, but it was constant. Always a door opening somewhere, or mobs falling from the ceiling. There was zero down time, except during the end event.
This can’t be normal.