Hey guys, for context I'm building a dungeon crawl set in a primeval forest for the first floor. I want to have the players interact with a Myconids colony as a social encounter, but I'm pretty bad at building social encounters with a point to them. I was hoping to draw a bit on the collective for help here.

The Myconids grow sweet fruit, which they trade to the goblin and elf villages (other social encounters/groups in the dungeon).

One problem is that I want the encounter to feel relevant, and the players are all now in tier 3.

The combat encounters on this floor are related to dinosaurs, and one is a zombie T-Rex. I'm also using Egregore from Destiny as a necrotic fungal situation, if those help.

So, I would suggest that you 'wanting' the encounter with the Myconids is part of the problem you're experiencing here. 

Why do you want the social encounter with the Myconids?

Do they hold a piece of relevant information to further the quest the party are on?
Do they know a shortcut, or about treasure in the area?
Do you just think it'll be fun to roleplay myconids?

This ultimately is where we get issues when designing encounters as DMs. I know I do it.


When designing encounters I tend to work backwards. 
- What is the goal of the encounter?
- What challenges exist?
- Where is the encounter set?
- What creature type best suits this environment and encounter?

So it may end up looking like this:

Goal - To retrieve the key to a storehouse where the adventure macguffin (an amulet) is stored.
Challenge - The creatures have buried the key along with other items from humanoid societies.
Challenge - The creatures are wary of humanoids - they tend to bring death/injury/etc
Environment - An underground forest of fungal growths. The air is thick with spores that if a humanoid spends to long in will poison them.
Creature type - Myconids, snakes, and other poison loving creatures.

The session might then play out such that the party have three choices
1. Break into the storehouse without the key
2. Try to win the myconids over socially and get provided with the location of the key. (They may even have to complete a quest to win over the myconids).
3. Slaughter myconids until one of them reveals the location of the key.

As to challenge and relevance, try to consider the myconids here not as valid enemies, but rather the same as you would a village on the surface. The average commoner is a weak and puny creature to most adventurers. In this the myconids are no different. So I'd advise setting it up in much the same way. Thing of the sovereign not as the literal stat block but design them like you would the king of a humanoid city. They aren't ever going to be persuaded to hand over their crown to an adventurer no matter the number that a dice rolls. The sovereign should be the same in that respect.

Unfortunately, without knowing more about the larger adventure arc that the player party is on it's difficult to advise beyond that I'm afraid.