• If you use both WASD and arrow keys at the same time, you move faster. This could be helpful in some sections.
  
  
• You need to have collected 5 coins to pass each level by the end point.
  
  
  This is what the coins look like.
  
  
  
  
  
  
  
  This is the end of level portal.
  
  
  
  
  
• On level 1 you keep any coins you collected if you die. This is the only level that does that.
  You could collect a few extra coins quickly so you don't have to worry about missing any in the later levels.
  
  
• On level 10 (final level), you do not need to have 5 coins.

If you have 5 coins ready, you can just wall jump up the box and finish this level very quickly without hitting any extra switches.