It doesn’t use controller configuration by default, so feels right at home on a Steam Deck. The mouse-and-keyboard layout on the buttons and trackpads gives it a lot of utility.
It seems that games which claim to be “Steam Deck verified” actually mean “controller verified”. As in it only shows controller inputs in the game. But the controller is only one small sample of what the Steam Deck can do. KBM works just as well on it if not better than standard controller layouts.
I have never played Rainbow Six Siege.
