Tuesday, July 6, 2021

Underneath - Resolving Differing Realities

These rules are for use with the Underneath system, which makes use of a sanity mechanic to potentially have different player-characters seeing the same thing differently, simultaneously.

It's assumed that we're working within the horror genre here, although I suppose the same arbitration/narrative issue will crop up when dealing with any sort of diverged realities- be it hallucinogenic drugs, magical illusions, or whatnot.

When you're at the table, one of the unspoken assumptions is that all of the player-characters are essentially experiencing the same reality. This is derived as a matter of convenience - one Game Master, one reality. Having multiple realities simultaneously present necessitates a kind of narrative juggling which can be difficult to manage.

And in my experience if two realities are being experienced, the players will poke at it until it stops or they give up and leave. This can be difficult to narrate and reconcile. So here's a procedure for Underneath to help you as a GM.


Group A experiences "Reality A", Group B experiences "Reality B". How do you resolve this difference? Do you resolve it?

There are four possibilities for how it can resolve:

  1. Reality snaps to A for everyone.
  2. Reality snaps to B for everyone.
  3. Reality remains differentiated.
  4. A Synergistic Reality - A-B - comes into being.
And because we're working within the Horror genre here, Reality A-B on average is going to be the worst option for the PCs. They'll find they really don't want A-B, and that'll hopefully drive reality towards a tablewide consensus.

Underneath Resolution Rules

i. If neither group acts upon, acknowledges, or undeniably interacts with their reality, then both realities remain differentiated. Sound of a tree falling alone in the woods.

ii. If one group declares their reality and the other does not acknowledge it, reality snaps to the side that declared.

iii. If both groups declare their realities to each other, then we enter into conflict. When this happens, they argue with each other and to the GM upon which reality is more believable. The GM acts as an arbiter, but not a judge, facilitating and encouraging roleplay. If a consensus among the players is reached reality snaps to that decision.

iv. If both groups declare their realities and cannot come to a consensus in a modest amount of time, a Synergistic Reality comes into being.

Synergistic Realities


Synergistic Reality



Reality begins shifting back and forth between the two. In the chaos a Wandering Encounter is drawn.

If this Wandering Encounter also produces a Synergistic Reality then all Players immediately become Lost in Space and Time.


Reality begins frantically tearing, opening a widening hole in reality. All who remain by this hole are Lost in Space and Time.

All players who don’t immediately begin leaving will get sucked in.


The area or creature simply disappears. It returns in 4d6 Hours.

If it’s a place, space neatly folds around it. All NPCs have no memory of the thing.


The object is now called ‘Something Incomprehensible’ by the GM. Something Incomprehensible crawls out of the object like a hatching egg.

Eyes and wings - too many eyes and wings. Unless all present characters prostrate themselves or avert their gaze, everyone immediately wakes up the next day with their Insight scores +3.


Things begin to glitch. The Glitched Man inconspicuously appears. Whoever next discusses the object will become infected with the Glitch. 

Each additional discussion on the topic advances the Glitch injury one step.


A true synergistic reality appears. The object is now a hybrid of the two realities, a conglomerate of aspects of each. It becomes Something In Between.

Something In Between has 4 HD and alternates its low Insight and high Insight behaviors. Its injuries permanently reduce one random stat each time it hits. 1d6: 1. Resolve 2. Instinct 3. Body 4. Empathy 5. Insight 6. Resources.


  1. Shenanigans as you begin to add additional realities (Reality C, Reality D... Reality n). Multivariate reality calculus.

  2. This is the most terrifying answer to the question you asked that could possibly have been produced.

  3. Additional fun rule: any metagame discussion by the players discussing which reality they'd prefer (as players instead of roleplaying characters) immediately spawns a synergistic reality.

    1. In a way it is appropriate - because metagame already exist outside of the game reality but overlaps with it, in a way being a mix of out of- and in-game knowledge.

  4. Damn bro this is some good shit
    Like damn