Here's a critter I've been dropping hints at for years in my campaigns but have yet to design..... A yellow creeper,/pod person plant abomination from far realm. Also loosely based on some ideas from Moanders followers from Forgotten Realms Finders Stone trilogy. Basically you encounter a corpse with flowers growing out of it. It has pods and blooms get too close it sprays you with pollen. Fail a con save you're infected. Then there are stages of infection. Phase one you feel a bit sick and gain a level of exhaustion and restless sleep. You then have to make a con save every 12 hours. Make three infection leaves system..... Advantage if more than hundred miles from one of the plants.... More on that later. Fail and move to stage two. You are now plugged into a telepathic network and under it's control. It has access to your memories skills and abilities. You appear to feel better but maybe look a bit pale or greenish. During this time you try to gain information and get closer to those around you learning their secrets. Again every twelve hours a con save. Fail and move phase three. Phase three. A vine or flower erupts from some orifice on the head... usually the ear or nose. Sometimes from a hole in neck. Now you can communicate telepathically at a range of 60 foot with and other mobile infected and several miles to mother plant. 12 hours later another con save. Fail and you die. Over course of 1d6 hours the flesh dessicates as a new pod emerges and grows flowers becoming new node in network. After 1d8 hours after flower grows it ready to infect. This mother node is immobile but forms a telepathic network with all other nodes within 100 miles. Storing information for all it's previous hosts.

Head cannon this this is from far realm. It was at some point discovered by Gith. After learning how to deal with it and losing a few settlements they weaponized it against Illithids. Using it to strike against several mind flayer strongholds. Illithids are well aware of this threat now as are beholders, grell, and aboleth. It was used in early Gith civil war. It is now just a foot note in history of githyanki who destroyed all they had weaponized after it got loose a few times.Also due to psionic and immobile nature of node plants they have access to psionic in nature spells until we get legit psionics.  The way I've used it is normally a crashed spelljammer normally illithid as source of infection. Usually somewhere secluded like an island.  Last campaign as homage to the "thing" the party found a derelict research vessel from a college of magic and they had been cataloging a strange sickness on a savage island and brought the corpse of an orc aboard. One of npcs gets infected and hijinks ensued.

Looking for critique.  Ideas likes or dislikes.  

What happens if you succeed on any of the saves?

Edit: Also, how is it a headcanon if you made it? Headcanon is how you think of something you do not have control over. Canon is how it is defined by the creator. Headcannon is a hat that shoots cannonballs.

Hi there

Glad you asked. 

If you make save at initial infection the you avoid infection altogether.   Phase One is the most complicated.   

Phase One basically you have to make or fail three con saves.  Each save is done every 12 hours of game time.   The to

If you make the save you recover but still have a level of exhaustion.

However fail three and you move to Phase 2.  Phase 2 and Phase 3 making a con save every 12 hours prevents you from moving to the next stage.

This falls in line with the goal of the mother plants to spread far and wide spreading it's telepathic net.  

The saving grace is the node plants are  largely immobile and I think I'd give fire vulnerability.

Obviously the more nodes and more infected the bigger the threat

It sounds like something from raising dion but it sounds cool