Hey thank you for the comment and it feels great to see that you liked this game.
It is a rogue like and we wanted to make it like Binding of Isaac, our apologies we forgot to add some controls informations in-game and on the page.
WASD to move the player, E to interact, SPACE for the fusion menu, and enter to valid and finally arrows keys to shot.
It sounded so natural for us because we really like Binding of Isaac and thought that it would be easier, but it is not really when we finally play it :/