I would have acknowledge the inspiration of the early grandfather of the genre, except that the "Company" apparently disapprove.

Gyaku is a variation of the name Jack. That it also means something like 'reverse' in Japanese is a bonus.

The game uses LocalStorage to save completed levels to make it possible to play part of the game and come back and play the rest at a later time without having to start from scratch. Some privacy settings of some browsers will erase the content of LocalStorage on closing the browser which will remove that function.