3 spawners are around the map, each having a zombie spawn egg inside. These will work as your ‘wave’ spawners.
I myself have tried the map and am going to say that if there are vines leading straight up to a house roof, the zombies can climb it. Be careful!
Upcoming Updates
I will make the map larger with lots more houses, and maybe soon there will be chests that you have to grab loot from to refill.