Monster synergy. It’s something I do not hear all that much. Surely we all know different goblinoids work together, or creatures like ettins and ogres work for others for the right bribe. We see lesser animated undead like skeletons or zombies work with each other or the creature that animated them, but not with something equally mindless. Way back when I first started playing the world’s greatest roleplaying game, what are now considered “dungeon hazards” were monsters. Slimes, molds and other colony based organisms were included alongside other monsters and added to wandering monster tables. You could stumble into a growth of them while walking about. Organisms like these can prove deadly, but lack the ability to move on their own. This doesn’t prevent them from growing on something with its own mobility, provided it could be a viable host. It is entirely plausible for overgrown dangerous mold growth developing on zombies. The trick would be explaining and delivering this encounter in a way both unpredictable and believable.
Encounter Type: Combat
Map: Dungeon room encounter map
Lighting: None (single room encounter.)
System: 5E
Length: One shot
Installation Type: Addon
License: Roll20 End User License Agreement
(Personal Use Only, Do Not Distribute)