I play Wizard101 often and I do the proper updates so that it runs correctly. But I've been noticing that every time I play, occasionally the screen will just flash black for a moment then go back to normal. I've been wondering if this is common for a lot of users and if not, how to fix it and what it is.
About your black screen flashing occasionally problem, I too have noticed this just one time once my friend helped me defeat a boss.
He cast a spell and after the twirling from his wand, my screen turned black and I could not see anything that he casted. It turned back as normal after the spell was done but that was the only time it had happened to me.
Angel Hex, Student in Balance, Storm and Myth magic.
You could adjust your graphic settings to the lowest possible state or even delete Wizard101 from your computer and then re-download it back. Either way is a solution that you may try.
Angel Hex, Student in Balance, Myth and Storm magic.