blogpost about the bugs
https://community.amplitude-studios.com/amplitude-studios/endless-legend-2/blogs/972-necrophage-spotlight

tl;dr
>only have one city but can build tunnels and hives for fast travel and adding territory
>units additionally can eat tiles and permanently boost the city
>units start as larva that you then evolve
>corpse resource for winning battles, razing cities etc. to evolve units, build special buildings, get more population etc.
>no diplomacy with minor factions