-1
While this may be EULA compliant, (not 100% sure) there is no real use for it. I don't use a point in being invisible for even a few minutes, and it would be abused in wild. I don't see a really good use for this overall. It'll also be really complicated and unessasary to have you turn visible when you get hit.
Plus, invis potions are already disabled in most places, and this would just completely reverse that.