The game was very well done. Love the power ups. The controls are not very intuitive. Space for jumping , LMB for attack.
I play Diablo IV, and World or Warcraft they both use numbers 1-4 for controlling the special abilities, placement of the mouse cursor for movement, LMB, RMB for special attacks.
You should try that. Put a little abilities bar on the bottom of the screen to show CDs and which button controls which ability.