You're Doing Vision All Wrong

Artist: Daniele Randazzo

GM: You hear a shuffling noise somewhere down the hall.

Player: What do I see?

GM: Nothing, just 60 feet of hallway and then darkness.

Player: I move down the hallway.

GM: Once you get ten feet down the hallway, you see a goblin 60 feet away from you.

This is how vision, or at least vision in the dark, is almost always described in RPGs: either you see something clearly or you don't see it at all.  In more mechanics-heavy games like 5E this is actually explicit in the rules, but I see OSR referees doing it too, perhaps out of a habit carried over from 5E.

This obviously isn't how vision works; things should come into view gradually.  But it also isn't conducive to tension, fear or mystery.  That intermediate step of "you see a shadowy figure that you think looks humanoid" is nerve-wracking.  It gets under players' skin.  Without it, vision is mostly just information.  

So, add it back in.  Have a level of vision in between "you see something and can tell what it is" and "you can't see the thing at all."  

I brought this up on reddit the other day, and someone told me that AD&D actually had vision chart that worked this way.  Here it is:

These should be self-explanatory, but just to be clear:

Movement: You see shadows/figures moving in the distance.

Spotted: You see something you think looks humanoid.

Type: It's a goblin, or maybe just it's a humanoid figure that's clearly smaller than a human and proportioned differently with longer limbs.

ID: You recognize Tom the goblin.

Detail: You see Tom has a bruise on his cheek and a small tear in his shirt.

So, my suggestion: retype this chart and order the rows from best to worst, or make your own chart.  Personally, I might remove all of the mist and fog rows, and only have rows referring to levels of light, then treat mist and fog as modifiers, like light fog cuts all vision ranges by half, moderate fog by 80%, heavy fog by 95%, etc.   

Then instead of treating darkvision as having a very specific range, treat it as shifting you up a category– from moonless night to full moon, to twilight, to day, or whatever.  Better forms of darkvision like drow and svirfneblin have could be two categories, and spells that grant darkvision could stack with natural darkvision.  

If you shift one level above daytime with clear sky you're fine, but two levels above it and you're blinded by the light.  

This will make vision far more realistic, but more importantly it will change the feel and playstyle of your games.  Half-glimpsed figures will inject some real fear and tension into the game.  It also gives players more choices about the risk/reward tradeoff of getting a better look at things: do you move closer to the shadowy figure to see what it is?  Hide and hope it hasn't seen you yet?  

It makes night feel like night, and dungeons feel like the creepy, hostile environments they're supposed to be.