Just now the gun doesn't seem happy to aim at the floor, which does rather limit the options for chicanery. Left click and right click, just as our Lord Gabe intended. You control Mari0 with WAD, and aim the Portal gun with the mouse. I think that might be something to do with the lack of programming for mushrooms at this point, meaning Mari0 is always on one life. A German, Maurice Guégan, and a Slovenian, Sašo Smolej, make up the team who say they aim "to create enjoyable experiences for anyone to easily get into and enjoy." Also noting that the sorts of people who might want to contact them are Nintendo, wanting "to send us a cease and desist letter?" I really hope they have the good humour not to, and recognise what is very clearly a tribute, not-for-profit game released as open source. Perhaps that's to be expected from an indie developer with the name Stabyourself. They're going to get sued into space by about fifteen different companies at once, but fortunately they don't seem to mind. It made me do that weird mix of smiling and frowning that Mario Bros games do, except with the bigger grins for clever portal application. I end today posting a genuine video of a game where two people are remaking the original Super Mario Bros, with a Portal gun: Mari0.
I began today posting a spoof video of the SNES's Mega Man, with a Portal gun.