You can upgrade your character's power and switch combat skills to deal more damage as the stages get harder.

Flash games typically save data locally to your "Flash Cookies" (Local Shared Objects). If you clear your browser or system cache, your progress may be lost unless you use a launcher like Flashpoint. How to download files - Internet Archive Help Center

En la página del proyecto, verás un recuadro a la derecha titulado (Opciones de descarga). Encontrarás dos alternativas principales: