While Thirty Flights of Loving was the sequel to Gravity Bone, it actually started first as a prototype for Gravity Bone. Developer Blendo games has released a video showing off the early version before it set Thirty Flights aside and oh, it's quite different. You can blast away with a submachinegun, for starters.
"Thirty Flights of Loving prototype (2008) had guns and dialogue and depth of field and a lot of bullets," one-man studio Brendon Chung noted on Twitter.
While the finished Thirty Flights was remarkably restrained--jumping about and trusting the player to understand what was happening, and having no dialogue but weird muted warblings--the prototype is barely recognisable, despite showing scenes from the full game. Text boxes pop up with exposition, characters give you objectives, and then there's that gun.