I'd think it'd be fun, but there's a few points i'd make.
like for one, instead of flat out no wards, how about
instead putting out that experimental mandrake ward on the pbe (rather nice if i say so). that way you don't know who is where, and you don't have vision, but you do at least know something is.
what about things that give vision, like with
? maybe if you reduce the summoner vision to 700 from 1200, you can make ignite make them visible within 1200, (fire can be seen in the darkness, after all.
I'd say pings would be needed, and teamchat. It would make communication very important to succeed, and if you don't communicate, you die.
i'd say it'd be blind otherwise, and it'd be fun to make it draft style, where you ban 6 champs in total, then make it a blind pick (kinda like in urf at the moment), but after you pick, you go into the game not knowing who you're facing until you see them for the first time. Kinda keeping the current version of how you don't know the enemy's build until you see them, but with everything, including teammates.
All in all, i'd say that it'd give the game a very nice, dark feel to it, but i think that certain champs (namely
with his ult and champs give/depend on vision to do things like
's hawkshot,
q,
ult, etc) would need to be looked at to see how they could be modified. like maybe their abilities could give slight vision if used within their live sight range (going back to the ignite giving sight in 1200).
Idk, all i know is that it sounds fun as heck