No. . . no one believes that Putin has played all his cards. . . and that is the danger.
Could he use tactical nukes? Or could he use Thermobaric weapons? What about other biological or chemical weapons if he gets desperate if the advance gets bogged down?
Russia is a very old and advanced military power. . . it might even have weather weapons, though, I believe these are also banned by treaty, but it is possible these could be deployed to cause storms and earthquakes as well.
Or he could shoot weapons into space to take out the satellites, severing communications, finally, launch some global thermal nuclear warheads?
All manner of chaos which folks cannot imagine, could, theoretically be unleashed. . though I doubt it, mostly because the most advanced weapons would be left in reserve for the most cataclysmic escalation of global war. . . with, well, the most powerful nation on Earth. . .