When I Made Things So Big They Actually Failed in Worldbox

I made a map as big as I possibly could because I wanted to see if a small group of zombies could defeat it. To start I dropped in 1000 humans and orcs on opposite sides of the map to let them spread out naturally. Of course this fails to have the desired result so I end up giving them some assistance. Many hours later my map is full of villages and thousands of residents. The zombies started out very promising, then kind of just.. did things. Worldbox gameplay with my commentary as always!

Worldbox - https://www.superworldbox.com/

PC Specs - Intel - Core i9-9980XE 3 GHz 18-Core Processor
2xNVIDIA - GeForce RTX 2080 Ti 11 GB Founders Edition Video Card (2-Way SLI)
Asus - ROG RAMPAGE VI EXTREME EATX LGA2066 Motherboard
Samsung - 970 Pro 1 TB M.2-2280 Solid State Drive
Corsair - Vengeance LPX 32 GB (2 x 16 GB) DDR4-4000 Memory