14 hours ago, Doomofman said:
When I watched the trailer I noticed that staged scene as well.
Though your picture is not showing what is possible. A wandering horde (in A21) can have 12 zombies (if I looked in the right place).
There is a small hope in my mind that the event system might make the trailer scene possible in actual game play. Vanilla code allows 64 concurrent zombies, more than enough for that scene, the difficult part is getting that many zombies to show up outside horde nights.