There are challenge runs, and then there's "I'm playing Sekiro by hitting the Rock Band drums with my feet" -style absurdity. HandowShandowed on YouTube is indulging in the latter, with multiple video uploads showing them playing Hollow Knight and Silksong at the same time, synced to one controller.
My inherent distrust after years of being lied to by the internet urged caution at first, but HandowShandowed looks legit. For one, they have a library of Hollow Knight challenge videos going back years, and while they never explicitly lay out the setup they use or show real world footage of their inputs, their gameplay footage across the two Hollow Knights is synced perfectly.
