Added: Health! You now have 1 heart to start with in all test rooms and play test rooms. when you touch an enemy you take half a heart of damage each hit. There is also a heart collectible that gives you 1 more heart. There is one in Test Room 4 and halfway up Play Test 2.  You can only collect it once and still lose half a heart giving you 3 hits you can survive. You can now press the SPACE bar in the web version to jump.