An ultimate ability which momentarily "flashbangs" your opponent's screen, for maybe 0.5ish seconds they can't see, the visuals of which could be darkness, a bright light, smoke etc. Afterwards for a secondary duration the following effects occur
Health bars for all characters are disabled, including your own. They could either disappear, or the numbers replaced with question marks and the colour changed.
All heroes, ally and enemy, now appear to be the hero that cast this ability.
Damage/hit feedback either doesn't occur, or occurs even when your bullets "hit" an ally, however no damage numbers appear and allies don't take damage, you are just wasting bullets firing at the wrong person.
Targeted abilities and items do not work during this time.
Obviously, other characters using abilities will reveal who they are, and altering their bullet types might be too confusing. I can't think of clear solutions to those problems, but this ability is meant to disorient you for a few seconds, it doesn't have to fool you for a long time and the disabling of useful information like how much health you and enemies have, and of targeted abilities would make it useful even if the person isn't fooled, such as in a 1v1 or if they see some abilities used right after their sight is restored.
