Make blindness crippling (and not utterly disabling)

[warcrimes]

what if it made you totally unable to see but you can right click on tiles directly adjacent to you to "feel" your way around?

I'm cool with that. Let it use the old knocked out effect where your vision fades in and out so you can only see every once in awhile but you can still click on stuff.

Take the same type of proc that throws you off of segways / skateboards and have it give you a brief glimpse of whats around you. 
Literally learn the room by smashing your shins into the patio furniture.