Nice made-in-spain game, here's a cheat for you all:
In the title screen type QWERTYUIOP: the message "Cheat keys (F1-F4) activated" will appear. During the game, press one of these keys to do the desired effect:
F1 - Restore the energy lost.
F2 - Increments money by one gold each time pressed.
F3 - Increments time by 3 seconds each time pressed.
F4 - Jumps to next level.
So, a good approach to finish the game is, at the end of level one increment time and then gold, for the time you enter the store. And, as some said before, please buy the axe!!!!
Have fun!!!!