Give Music Sheet #23 to the Bard in the Village, and he will say "My first publicly performed lair theme. You might say it Kickstarted my career!"

Enter the Hall Of Champions, and look at the portraits on the walls. Each of them represents someone who donated at least $200 to fund the game's Kickstarter project.

During the ending sequence, you can see five enemies grouped together under the name "The Wandering Travelers." These enemies were actually created by five people that participated in a "Director For A Day" reward for contributing at least $1,000 to the game's Kickstarter project. They are the "Liquid Samurai" enemies; Reize, the Phantom Striker, the Haberdasher, Mr. Hat Boss, and Baz.