- Heartbeats and ambience are pretty good
 - Keys, keys, more keys. Not a fan of WASD + JKLI at the same time plus many more for single interaction purposes. Looking at stuff could be bound to WASD + modifier, like CTRL. Or mousecontrols, although looking at this scheme you most likely excluded that on purpose
 - Also keep in mind that with an international audience the keyboard layout may differ from yours. Allowing rebinding would be useful
 - With both hands laid on the keyboard, not being able to use Space additional to Return in the menu is frustrating. You allowed it for text advancing, why not here as well?
 - Found myself challenged by the riddle portion. Good stuff
 - Stylistically well done. You know how to keep it simple (visually)