Now that the PS5 has launched in a few lucky homes, it's clear that Sony's promises were right. Some, like The Last Guardian, run much more comfortably than when played on the previous generation of hardware.

But it is also clear that Sony's official list of 10 unsupported titles does not tell the whole story; a mysterious web page pulled by Ubisoft suggested as much, and now it has been confirmed.

According to Kotaku, "approximately 115 games" in the U.S. PlayStation store include the following warning: "When played on PS5, this game may have errors or unexpected behavior and some features available on PS4 There is a possibility that this may happen."

This is annoyingly vague. For example, there is a big difference between not being able to play multiplayer and having a bug that causes the game to be over 20 hours into an RPG. Unfortunately, this is the only guidance we have.

More confusingly, when Kotaku did unannounced checks of some of the games on the list, some errors were immediately apparent, such as the migraine-inducing shadow flickering in "Assassin's Creed: Syndicate" that was Grip" and "Pixeljunk Shooter Ultimate" both seemed to work without apparent problems, but personally I was left wondering when and how they would fall apart.

Other games tested by Kotaku were "Everybody's Golf" (the scenery flickered, but a patch will be released for the PS5 version), "Flinthook" (suffered from some slowdown), "Hellblade: Senua's Sacrifice" (there was some blurriness in the opening scene) were.

It is unclear what makes the games on this list different from the others, but if you want to investigate your own PS4 game collection, you can use this Github tool to narrow down the titles with backward compatibility warnings: drop down "PS5 BC" to "bootable Simply change it to show all titles with warnings.

After all, the PS5 has a pretty strong lineup of launch titles to keep you busy. But before purchasing additional PS4 games to play on the new hardware, it's definitely worth inquiring online to see if they work as expected.