ID:1929244
 
Ideally id like the entire screen dark unless their is a light source. Obviously this is easy with built in things but I'd prefer to make it round sorta like https://www.google.com/ search?q=horror+sprite+game&source=lnms&tbm=isch&sa=X&ved=0C AcQ_AUoAWoVChMIvOfm0KLXxwIVlDaICh0gLQNa&biw=1525&bih=729&dpr =0.9#imgrc=qMQ1NHUsjrZnaM%3A this, but with other light sources opening up light as well.

Is something like this practical with byond? or should i just give up and focus my vision to something more plausible

It's possible, but in my opinion if your game is multiplayer, you should avoid the hell out of it.