This happened twice for me today. Earlier, I can’t see most of enemy characters. I thought I was lagging because Battle net was downloading future patch in the background.
Tonight it’s happening again (on different PC, so it’s also downloading in the background) but this time I can’t see my own character model, UI and effects, and some other character models both in my and enemy team. The environment was also blurred like the background of hero select screen. This happened mid-game, by the way.
Both time this happened, after the match is over, the POTG was just environment with no characters at all. There was also no cards, scores and any UI elements, just background environment.